Some future artists will make things that cannot be made by AI and some future artists will make things using AI. Unless you are arbitrarily deciding that the new definition of artist is "someone making art that explicitly doesn't use AI" which I suspect won't hold culturally.

As for the accusation that the only thing an AI can spit out is garbage, I think the classic cliché "garbage in, garbage out" applies. It is possible (and IMO likely) that the world will reward those who can get treasure out of AI and it will punish those who are only capable of getting garbage out of AI.

If you are the kind of person who believes that only garbage can come out of AIs then you will never be in the group that gets treasure out of an AI.