AFAICT, as much as YC was a child of their time, they (and PG) were also one of the parents of our current time.

I'm guessing it was inevitable that Wall Street would take over the field, and turn it into a machine.

And therefore it was also inevitable that people who, in the past, would've gone to Wall Street, now would flow into the space, and take it over.

But YC did put their own spin on that, in which the traditional affluent-family, prestigious-school kids could also be computer nerds.