But they aren't more successful. They can solve this because of standing on a huge body of work made by working mathematicians. Without it AI would get nowhere. Now AI are burning the minds that fed it for short term gain.

When AI has exhausted the existing math literature (and found a bunch of errors, I'm sure) it will have to start producing its own conjectures. Millions of them, even billions. And using all the experience from trying to prove them to improve.