When I joined ST fandom in early 1980, I had diehard TOS people telling me that TMP left them feeling "empty" and "unsatisfied". I spent many months trying to defend a film that all of my new friends thought was a boring piece of crap. I heard the exact same criticism from others re ST II (in fact, there's a whole thread on this over in the ST Movies section). Ditto ST III. Other fans have told me that they felt ST IV was a dumbing down of the franchise for the masses and that it left them feeling "patronised", "empty" and "unsatisfied".
Why is TMP better? Well, it has a certain majesty to the way it was filmed. It was treating TV material to the benefits of a huge motion picture budget, and a three-to-six month principal photography shoot - when the cast were used to filming a one-hour episode in less than ten days. It was reuniting a cast who hadn't worked together in a decade. And the production design and direction put me, a lowly member of the audience, who knew very little about the characters and their previous adventures, onto that ship!
It's hard to describe, and it was made worse in 1980 when I couldn't find many TOS fans who actually liked TMP. For me, who was also lucky enough to have already read the novelization! - it became a film that fully submersed me in the action.
JJ went quite close. While I never felt I was on that ship, I really did relate to the characters, and felt their losses - of lives they would never get to experience due to the changed timeline. Both films certainly rely upon a lot of nostalgia value, both plundering it to make us relate to the material, and rejoicing in it without a hint of self-consciousness, but TMP pips JJ at the post for the way it affected me as an audience member. Mind you, I was a naive 21 yo watching TMP, and a more seasoned, very Trek-knowledgeable 50yo watching ST XI.
You'll never please 100% of fandom with a ST movie, but this one probably went closer to that 100% than any other. Its high rating (currently 95% approval from 273 reviewers!) over on Rotten Tomatoes still staggers me. The backing of Leonard Nimoy was also significant. I also find it ironic that so many people now look back on TMP with a quirky fondness. That film that was scoffed at, as "The Motionless Picture", now has a secret niche in the soft spot of many TOS fans' hearts.
I've actually spoken to quite a few Sydney celebs and society folk who were at the Sydney Opera House world premiere of JJ's ST and they said that the praise for the movie, from the 2000 invited guests (and lucky 200 ST fans who were able to buy tickets to the premiere online), was almost universal. Standing ovations in many sections of the Concert Hall. Those society folk then went forth on Twitter, and their Facebook, MySpace sites and spread positive vibes to the world! Brave JJ and Paramount! Imagine if those 2200 people had hated the movie with a passion. Nobody was paying them to be positive about the film.
JJ promised us a ST movie that would reach beyond existing fandom, and get people talking positively about ST again. He achieved that. I felt it was a successful emotional rollercoaster of a movie; some fans managed to not be affected by it. C'est la vie, I guess! Every time I see the opening scenes I choke up. So do my friends. Nero's attack on Vulcan was unexpected and with amazing consequences. I find it hard not to be emotionally compromised!
If you didn't get anything out of the movie, I can only say you seem to be in a minority. And better luck next time?