This is a deeply cynical (not to mention, a touch misogynistic) take on human motivation. This might be true for your small circle of friends but I think it reflects your thinking a lot more than some deep objective truth about people and their careers.
If that is the case and I am wrong, how come there is a crisis in every math department? Why is Terrence Tao publishing copium guest blogs daily about the meaning of mathematics?
And Williams thoughts are kind of idealistic. "Now the credit is shared across the entire field". This "credit" does not give your department grants or further your own career.
Rather it incentivizes you to be the first one to prompt, and to steal ideas from your peers because you can prompt better and have your name on more discoveries.
I never claimed there isn't a crisis. I think the motivation of mathematicians is a mixture of prestige and genuine curiosity and understanding about these abstract problems. I think recent advances are creating a reckoning on how the community-at-large addresses these incentives. It is highly reductive to argue that the only motivation is as crass as you put it.
See professor Williams' thoughts on a recent conjecture that openai proved: https://people.csail.mit.edu/virgi/thoughts.txt