My reason for this somewhat provocative claim is that the nature of mathematics will transform by quite a bit once LLMs go mainstream for mathematicians. I see some posts here and there on X, but these are early adopters, mathematicians that are interested in ML. The large majority of research mathematicians hasn't yet much explored working with LLMs from what I gather speaking with professors at various universities.
Once LLMs go mainstream, I predict a lot of conjectures will be solved. This will generate a few years of excitement. But what comes next?
Probably a bit of fun will go out if mathematicians become curators of math knowledge (produced by LLMs) rather than producers of knowledge.
Some domains are already so well developed (parts of algebraic geometry), and the road to mastering these domains so long, that it may just become infeasible to even learn, as a human, what the frontier is - this will take out another bit of fun.
That's why, for humans, my long-term take is rather pessimistic: we will produce a lot more mathematical knowledge, more the ever before, but it won't be as fun anymore and probably fewer people will want to do it, and who is to say that the usual "escape to abstraction" that was often the way to resist automation, will resist LLMs?