- It's a very old universe that ain't broke, and that deserves our respect. Most superhero comics need to be rebooted every so often because they get ridiculously convoluted, lose all sense of proportion, or both. Star Trek, however, kept a nearly forty-year continuity with only a handful of modest acknowledged and implicit modifications. The franchise lost its way, sure, but it never jumped the shark.
But it is ridiculously convoluted.
Otherwise you wouldn't have people asking why some ship in the 29th century didn't come back through time to stop the events in the movie from happening.
That's what I mean by "implicit modification" - the viewer accepts a suspension of disbelief in that visitors from the future only show up and act when it serves the plot at hand. The Temporal Cold War
could have been a sharp-jumping effect, I guess, if ENT wasn't established as a prequel series that wouldn't
substantially rock the boat in any long-term way.
That said, the continuity still holds together remarkably well. It's complicated and stuffed, sure, but not convoluted in that with only passing exceptions, new viewers could join the party at pretty much any time without too much difficulty. The
X-Men series, OTOH, couldn't even do
four movies without getting their times, story continuities, and relationship stuff all screwy.
Does the first 40 years of Trek history deserve respect? Absolutely. But by making a reboot movie in the first place you are acknowledging that the original continuity is a burden to storytelling.
TPTB didn't consider a franchise reboot to tell stories with fewer restrictions; they considered a franchise reboot to tell
Kirk/Spock stories with fewer restrictions.
They could have gone in any number of directions post-
Nemesis with the existing continuity, and told whatever stories they liked; they just figured (correctly) that going back to the TOS gang would make them more money.