I don't see how this follows.

Saying that OpenAI does this only to show off their models, rather than also advance mathematics or at the very least their model's mathematical capabilities, seems speculative.

I understand OpenAI published write-ups for each problem.

It's unclear to me what other expectations mathematicians have that would demonstrate OpenAI's commitment to advancing mathematics.

Last I heard they asked to completely stop solving math problems with AI, which seems just ridiculous.