You might find them used to accelerate research math by helping them with lemmas and checking for errors, and formalizing proofs. That seems realistic in the next couple of years.
I'll bet the most technical open problems will be the ones to fall first. What AIs lack in creativity they make up for in ability to absorb a large quantity of technical concepts.
Side point, there is no existing AI which can prove - for example - the Poincaré conjecture, even though that has already been proved. The details of the proof are far too dense for any present chatbot like ChatGPT to handle, and nothing like AlphaProof is able either since the scope of the proof is well out of the reach of Lean or any other formal theorem proving environment.
What I meant is that there's no AI you can ask to explain the details of Perelman's proof. For example, if there's a lemma or a delicate point in a proof that you don't understand, you can't ask an AI to clarify it.
Then again, it's fairly likely that P=?NP is decidable but we just don't have any idea how to prove it. In that case the question is more or less "what's the time horizon until AI is vastly better than humans at formal math?", to which the answer is certainly "we don't know, there may be obstacles, just wait and see".
For all we know, buried deep in AlphaProof's attempts to solve these toy problems, it already tried and discarded several new ideas.