[vkazanov]

I know a PhD specialising in applying ml algorithms to different markets, mostly energy-related.

Married, 3 kids, good position In a fund, same focus as his phd.

He was very, very lucky, without even realising it to this day. His wife took most of the hit, with him permanently working, or teaching, or something, and her taking care of thr rest of their life, kids included.

On the specialisation side. He never went the "pursue a dream even with no money" way. It was more about picking things he was good at, and also making sure the choice included sellable skills.

[bombcar]

The number of these you'll find, especially in teaching, is amazingly high.

The "absent-minded professor backed by his down-to-earth wife" is a trope but a common one (and, to be fair, it's not always a man who's absent minded!).