So it's also OK for the GM to have buy-in on what characters the Players have? "You want to play an elf ranger? How about a human thief? No? What a jerk."
Sigh. No. It's an exercise in consensus seeking. If the player really one thing A, but the GM doesn't, then there needs to be negotiation. If negotiation fails, then no game. If a sufficient majority opinion forms, that's the ticket -- dissenters can then agree or go their separate way. In all of this, the GM is not privileged. The very question you pose assumes the GM has some moral authority they should wield here, when what should be happening is a group of players picks the game they all most want to play together.
The very idea that the GM has authority over this negotiation is edging towards abusive. It's the GM acting as dictator over something outside of the game -- the very choice of game to begin with. In this, the GM's opinion is equally valid as the players. Or, in other words, there's nothing special about the GM's creative vision that makes it better than anyone else's. In fact, the only leverage a GM actually has is the threat to not run a game. This is usually coupled with long indoctrination that running games is hard, so players shy away from it, closing the gates to more GM's and allowing the existing GM to threaten to remove access to force their way on the group. If you think this is an okay way to act, well, we're just probably going to disagree.
Once buy-in is achieved, if a player goes against the agreed to framework, they're the jerk. And, not everyone has to buy-in, if the group majority wants Game A, and the dissenters Game B, they can go find it somewhere else. This is just like deciding to go bowling with a group of friends, but one begs off because they're just not feeling bowling tonight.