They're doing so by choice to do PhDs or go into public service. They (as in, the ones in quantitative majors and many even outside of it) _also_ had the choice to make several multiples of what I made by working at Jane Street or HRT or Citadel or now OpenAI and Anthropic.
I didn't have the choice. Nobody is selecting me for anything, I don't have the optionality of doing just anything. I took the best offer I got at a company that most elite school students would consider to be beneath them (Amazon).
Anyways, I'd also bet you make multiples of what I make now too as someone with a higher level if you're an SWE or adjacent.