Star Trek: Enterprise is a very divisive topic among Trekkers / Trekkies. Personally, I'm not a big fan. It was a perfectly adequate space adventure TV show, but just never quite worked as hard science fiction for me, let alone as "Star Trek". There were certainly some stand-out good episodes. The haunted space station of "Dead Stop" and the mirror universe antics of "In a Mirror, Darkly" being among my favorites. The annoying thing is that the show made several mistakes at very fundamental levels before it even got off the ground. I could have lived with the show being a prequel, but the efforts to make the show seem both futuristic to the viewing audience, but also less advanced than the (then 40-year-old) original series put the show in an awkward juxtaposition with established series continuity. The hackneyed time travel meta-plot certainly didn't help.
"Juxtaposed" is an excellent way of describing Enterprise as a whole. It's a show that simultaneously seemed ashamed of its "Star Trek" name (remember, it premiered with the title "Enterprise", and "Star Trek" was only stapled back on in later seasons), while also indulging in needless - and sometimes cringe-worthy - fan service (such as the appearance of the Borg, Ferengi, and the entire episode "In A Mirror, Darkly"). It wanted to distance itself from established Trek tropes, but also brought back many of the same technologies, concepts, and character archetypes (simply renaming many of them). It set itself at the cusp of development of advanced science fiction technologies, but completely waffled when it came to telling hard science fiction stories about those technologies. It wanted to be simultaneously a prequel and a sequel via its contrived time travel premise. It was this lack of confidence and true vision that really killed this show.
The science of future technology
The show made the mistake of trying to present a Star Trek setting that was less technologically advanced, but still went ahead and gave the crew access to stand-ins for all the established trek technologies. They tried to make the Enterprise itself feel more like a contemporary submarine with its confined spaces, but it never really felt different. There was "hull polarization" instead of shields, and "phase cannons" instead of phasers. Different names, but same basic concepts that were used in exactly the same manner. The crew didn't start the show using more contemporary-seeming projectile weapons - not even a futuristic projectile weapon like a rail gun - before transitioning to purely energy-based weapons. The Enterprise didn't have to be equipped with any kind of futuristic chaffe in order to misdirect hostile targeting scanners, nor did it use point-defense to destroy incoming missiles.
"Phase pistols" and "polarized hull" were just lazy stand-ins for phasers and shields.
The only pieces of tech that the show really held off on (and were relevant to narrative) were the universal translator and transporters. The translator was rarely an issue since Hoshi was practically a Babel Fish. The transporter was there, but it was not trusted to reliably transport living things - even though it had been verified as safe by the beginning of the first episode and was successfully used in that episode. So for most of the show's run, the crew used shuttle craft for away missions, but the transporter was always there just waiting to act as a deus ex machina to get the crew out of a sticky situation (which, of course, happened on multiple occasions - including the premiere).
The fact that these technologies were already in place made the show feel too similar to other Trek series, even though it desperately wanted to feel distinct. But it also prevented the writers from exploring some of the more interesting issues inherent to the development of these technologies. Again, the transporters are a prime example. When I first heard about the idea of a Star Trek prequel series, one of the first concepts that I started itching to see was an episode about the invention of the transporter and an exploration of the mind-body problem and the nature of identity (see my review of the game, The Swapper). Basically, I wanted an episode that asked the question "Is the person that get materialized by the transporter actually the same person who was de-materialized?" But that never happened. The closest we got was the episode "Deadalus" about the inventor of the transporter trying to reassemble the molocules of his son, which had been scattered in space by an accident in an early transporter test - basically Dr. McCoy's worst nightmare. The mind-body problem is something that has plagued the Star Trek transporter since the Original Series. It's always been dismissed off-hand by the existence of the "Heisenberg Compensators", but the reliability of this tech is muddied by transporter accidents and duplication that occurred in episodes of Next Gen and Voyager. The episodes "Second Chances" and "Tuvix" both explored this topic very well, and Enterprise had a prime opportunity to do [at least] a whole episode of its own on the topic. But it never happened.
Even more advanced technologies like the transporter were carried over, acting as deus ex machina.
Enterprise did have plenty of episodes dealing with contemporary social issues such as racism, gender identity, sexuality, terrorism, interactions with other cultures, and so on, and I don't want to understate those narratives. But at the same time, Enterprise generally flaked when it came to dealing with more hard sci-fi concepts. About the only real science fiction-like concept that the show reliably addressed was the adjustments that the crew needed to make for living in space. Even this I thought was half-assed. The crew already had the benefit of gravity plating, so the show didn't have to use centrifugal force from rotation in order to create artificial gravity, nor did the crew have to deal with weightlessness or other health concerns regarding extended time in deep space. At least, not until they reached The Expanse, at which point the show just started making up ad hoc anomalies with little or no justification. Granted, these limitations were probably compromises involving production costs for a weekly TV show, but clever set design could have gotten around those limitations. Such efforts would have grounded the show a lot more and made it a much better transitional piece between our own time and the time of the original series, as well as acting as a parallel to the risks that real astronauts and space explorers might have to deal with. Instead, it all gets glossed over.
Different universes, with different timelines
One of the best episodes of Enterprise ended up being the two-parter "In a Mirror, Darkly", which took place entirely within the mirror universe (complete with its own alternate mirror universe cold opening and title sequence). As much as I liked this episode, I was also kind of sad that it happened, because it nullified the possibility that the show would end the way that I had wanted it to.
"In a Mirror, Darkly" included its own unique cold start and title sequence.
During the third season, I started to suspect that perhaps this show's continuity breaks and different tone might have been more deliberate than fans had originally thought. In addition to being a prequel for the series as a whole, Enterprise was also a sort of "sequel" to the movie Star Trek: First Contact. We have speeches from Zefram Cochrane (played by James Cromwell in both Enterprise and First Contact) that mirrored dialogue from First Contact, and then eventually, we have the second season episode "Regeneration" that explicitly sets Enterprise within a timeline created by the temporal incursion of the movie First Contact. This set, in my mind, the idea that perhaps Enterprise isn't necessarily in the same past of the original series, and so continuity changes could be dismissed as the result of changes due to time travel.
Enterprise explicitly takes place in an alternate timeline established by First Contact.
But I also started thinking that the changes might go even deeper than that. The show, as a whole has a darker tone than most of the rest of the franchise. Humanity wasn't very trusting of alien races, and they saw themselves as being persecuted and "held back" by the Vulcans who were supposed to be their allies. There was a hint of mistrust and xenophobia right from the start. Season three's Xindi story arc started elevating this sense of mistrust and xenophobia that had been present from the beginning, and even added an element of paranoia that permeated human culture. The season four episode "Home" was all about the xenophobia infesting and growing on Earth. This thread was picked up later in the season with the Terra Prime arc.
The penultimate storyline of the series was about a group of xenophobic humans establishing a xenophobic, alternative government based around the concept of isolating humanity from the rest of the universe. The kind of government that sees aliens as second-class, if they bother to grant them rights or privileges at all. This ended up being a minor plot thread of the fourth season that appeared in the beginning, was mostly dropped in the middle of the season, then concluded in the end. But what if this had been the overarching plot thread of the entire season? Or maybe even the entire series?
Terra Prime shares a lot with the Terran Empire.
Imagine, if you will, a season four in which Terra Prime were a pervasive and elusive shadow villain slowly spreading its roots in human culture and Starfleet itself. It would exploit the humans' mistrust of Vulcans, and their fear of the Xindi and gradually radicalize a growing faction within human society. The crew of Enterprise would fight against this where possible, but their deep space missions might keep them too far away to affect any meaningful change. In the end, we have Enterprise and Archer being recalled to take part in the signing of a new governing charter - the Federation Charter, presumably. The top brass of Starfleet, members of Earth government, and ambassadors of alien governments living on Earth all gather in the council chamber expecting the founding of a cooperative Federation that Archer and his allies had been negotiating. But instead, Terra Prime soldiers storm the chamber, members of Starfleet and the Earth government turn against their comrades. They take all the aliens hostage, imprison Archer and the Enterprise crew, and replace the blue galactic-olive-branch flags of the Federation with red Earth-and-dagger banners, and declare the foundation of the Terran Empire.
Star Trek: Enterprise shouldn't have been about the founding of the Federation. It should have been about the founding of the mirror universe's Terran Empire. Reframing the entire series as having taken place within the mirror universe (created by the Borg's attack on earth in First Contact) would have been a clever subversion of fan expectations, and would have basically resolved all the continuity issues that critics had complained about: any perceived continuity errors would be dissmissable as the result of the series taking place in an alternate timeline, contaminated by tampering from the future. In fact, "Future Guy" (the mysterious person influencing the Suliban from the future) could even have been revealed to be a human agent of the Terran Empire - maybe even Jonathan Archer himself, or a familiar character like mirror universe Kirk or Picard.
The identity of "Future Guy" was never revealed (though he was likely intended to be a future Archer).
The whole series as a post-9/11 allegory and warning
This would have served the purpose of giving more narrative relevance to both the Temporal Cold War and the third season Xindi arc. Tampering with the timeline (and violating the Temporal Prime Directive) would have lead to the creation of the mirror universe, and the Xindi attack specifically (and the extremism that emerged from it) could be seen as the catalyst that created a paranoid, xenophobic empire, rather than a benevolent, cooperative federation. It would have served as a stark warning to Americans and Europeans of the potential outcome of post-9/11 anxiety and xenophobia towards Muslims and Arabs (and vice versa), and would have posed the question: what kind of future do we want to create given the path that we are following now?
The series went a little bit in this direction with the storylines of "Home" and "Terra Prime", but it failed to commit. In its attempt to rush to wrap up the series and tie it into the rest of the franchise, they basically dropped this plot thread and just tied everything up in a relatively happy little bow. Cutting the series short and reframing it all as being about ideals failing as a result of racism, bigotry, and extremism could have served as a bold and powerful message. It even might have reframed the show's opening title sequence and song (Faith of the Hearth) as a plea to maintain optimism and faith in ourselves and our galactic neighbors; a faith that the humans of this series had lost. The future is what we make of it.
In the end, Star Trek: Enterprise was sloppily conceived and sloppily executed. The lack of a genuine creative vision or plan for the series as a whole really hurt it. The show seemed to clearly lack focus with its meandering time travel meta-plot, and it never really found its own identity.