In Brave New World what are the disadvatages of John coming to the World State?
Like what has he done that has done damage to World State and himself being there?
John is clearly damaged by being brought to civilization. That's why he kills himself. He loses all his illusions about what civilization is like. He gets to go to what he thought was a great place and he hates it. That kills hiim.
The society would have been hurt if he stuck around. He was too authentically human with real emotions. The world state didn't want people like that. As it was, the state wasn't hurt badly. But if John had stayed around, it would have been hurt just like it would have been hurt if Helmholtz was able to stay around.