I somehow felt he, along with Andrew Ng, are very few well-known AI experts that are left behind on the money side during the AI-gets-me-super-rich crazy time, unfortunately.
Andrew Ng has been investing in AI startups for almost a decade, I would be very surprised if this rising tide left him behind.
I can't speak for Andrew Ng - but my take is he did out of pure altruism - love. just in terms of advancing free education e.g coursera & the free machine learning courses etc he brought to the masses.
not everyone does things to be rich.
Only if you think B is an important thing. He is easily > $100M from Tesla.