Personally I don’t have any moral objections to a sweeper. If you can win the game with 15 men back, that’s fine. A sweeper can have a place in hurling, because somehow a two man full forward line can be as effective as a three man if played correctly.
But I think there are other options to shoring up a defense. You can drop a guy back just for puckouts. You can play a deep midfielder, who can come up a few times a game, you can have the half forwards move between the two 45s as needed. Probably standing a guy back as a sweeper where he isn’t involved in the play is a waste of a guy.
It’s different if you are under the cosh and being bombarded with ball. Then you need to put people where the ball is going. But in a case like that you are probably going to lose anyway and it is just damage limitation, but that has a place too in some games