This is really an all-IPs opinion, not just for Star Trek:
Ever notice that when people argue for this or that thing that should have happened differently, or this or that way a story should have ended, their alternative offerings are usually either (a) something you’ve seen numerous times before in other stories, or (b) exactly where you thought the story was going until That Thing That Was Wrong?
Which is why, usually? That Thing They Did “Wrong” is what makes it this story, and not another more predictable one. Which is to say: not wrong at all.
People are free to dislike it of course — that’s true of any ending, or any story turn. But more often than not, to say it shows the writers don’t understand the story they’re writing as well as the angry fan does is… well, inaccurate.