This doesn't just apply to the wealthy, but more lowly people too: see "Engineer's disease."
People like Musk and Adreessen are getting hit by a double-whammy: they're software engineers (the stupidest and most arrogant class of engineers) AND they're massively wealthy.
One curious thing. My country was erased from maps for 123 years (Poland). During that time, universities in all three occupied parts could freely teach engineering, physics, math or biology. Occupiers didn't care, they even wanted to have access to talent pool of specialists educated on these universities. On the other hand, teaching of history, philosophy etc. was highly controlled and restricted.
One can wonder - if humanities are so useless for the society, why did they even bother?
But the simple fact is, nobody's a genius in all areas. We all have our areas of expertise, but none of us can be trusted to speak wisely about all things all the time.
At the same time, as others have said, your BS detector has matured.