I see the big divide between those who do and those who don't differently. Most people choose a life pursuing happiness, a few choose lives of meaning. The person who chooses a life of meaning wants to get rich, but they secretly don't do it for the money. they simply can't not do their dreams. To most, it's foolishness. It's not that the person choosing a life of meaning doesn't want to be happy, or can't be, it's just that their happiness is largely irrelevant.
I also disagree with the crap about age. PG filters everything through this fine mesh, then claims the result is representative of the whole. I realized sometime around age 40 that to those who see startups as foolishness, there IS NO GOOD AGE. I kept wondering how I could go instantly from being too young to being too old. According to most, there is no good age. It's always a bad idea.
What PG is experiencing is this. Much of the corporate World, and the homes of families in which people grow up, it is heavily permission-based. In the Midwest for example, anyone behind a tech startup is considered out of line because they didn't ask permission, they didn't spend twenty years climbing a permission ladder. If they succeed, they are thought to have broken the rules. Younger people are more rebellious - we don't need no stinking permission - and can succeed if they don't first spend years working for a bunch of mindless droids.
Yet, it is still far superior to have broken through all this and risen above it all, to have endured the worst and still plow ahead in relentless pursuit of meaningful dreams to build something great. Meanwhile, there's PG with his clipboard going up and down a check list. I plain know better.