Edit: I take your point about capitalism but the thing is, sometimes hard-nosed optimization is suboptimal. That is, sometimes narrow self-interest ends up limiting you, and sometimes going against self-interest (as currently perceived) leads to greater outcomes, like navigating through a narrow waterway and ending up in an ocean.

This is what happened with YC. The YC founders (not just PG) consistently did things that the rest of the industry thought were stupidly self-limiting. For example, if the founders of a startup wanted to get acquihired, YC would say "great, do what you think best", where other investors would say "over my dead body" because they weren't making money on the deal. YC's attorneys in those days would send the paperwork back because they thought there must be some mistake.

It turned out that optimizing for founders optimized for YC as well, but this was not so obvious at the time. Why did pg and YC do that? it wasn't because they were "good capitalists". It was because of the kind of people they were and the ideas they thought were cool. That turned out to be massively more profitable than being a ruthless capitalist would have. So in the end it gets a bit hard to draw these distinctions. Sometimes being a good capitalist makes you a worse capitalist!