This guy was never a developer. He was a founder and CEO with a successful exit.
He was hired as a former founder and CEO, by a business working in the same space in which he was a founder and CEO.
It's an interesting story, but unfortunately its relevance to the career trajectory of the average tech old-timer is somewhere close to zero.
I think you see a high correlation between being a founder and having really strong opinions because these people can afford their opinions, both literally and figuratively. They don't have to live in fear that their opinions might leave them unable to provide for themselves and their families.
If the takeaway is "If you want his confidence, then become an entrepreneur," I am very okay with that. There is zero reason we can't create a country of lots of small businesses and consultants. The reality is small businesses provide more jobs and job growth in the U.S. than megacorps do anyway.