Every new mathematician that comes along doesn’t know everything that has come before him. He needs to go learn all the math that his predecessors did. I don’t see how an LLM coming up with these proofs changes that.
Because the problem space is basically infinite. If a person is working on a problem, its probably interesting to at least one person. Randomly walking through the problem space might be interesting, but I don't know how the signal will fare against other humans.