When people express a dislike for FF7's ending I think it's madness, as FF7's ending is great. Sephiroth is stopped, the planet is clearly saved, but the game is ambiguous as to if humans survived, because as Bugenhagen predicted/theorized early in the game, holy might choose to kill humanity because of how much of the suffering on the planet was inflicted by them. There's the children's laughter at the end too, which is just a hint, but given that it's hundreds of years on it's all really pretty open.
I really loved that ending in its ambiguity. It commanded people to think a bit. Fuckin' killed by the terrible sequel stuff though.
I like FF15's ending for the opposite reason though. After all the bumbling the game does, the ending is very conclusive and plain apart from the question of if the guys are dead (but get real, they are).