Lots of universities train people to be able to work at startups; but only Stanford (and, distantly behind it, MIT and Harvard) trains people to own them. Very few schools inculcate the confidence, as a 22-year-old with no work history, to walk into an investor's office and ask for a million-dollar seed round. But at Stanford, where seed investment is a graduation present, that's normal to people.
The rest of the country has some fierce talent and there are capable people everywhere, but there are only a few places where it's normal for people to think of being a founder as a logical next step. Merely working at a startup isn't the same thing.
I think this can be overcome. There's a lot of talent outside of a small, privileged echo chamber and there's no good reason why it should be excluded from the highest levels of work autonomy. I'm just pointing things out as they are now.