Silicon Valley investors basically just invest randomly in people based on their membership in a club. It's only because a small percentage of them turn out not to be complete idiots that it works at all. The smartest of the 99% receive no funding, while the entirety of the 1% wealthiest do.
It's an insider's club built around the "top schools" (as they call themselves). You're either in the club or you're an outsider, and only a handful of token outsiders are needed for display purposes.
If you want help in Silicon Valley, you must have either: 1) a rapidly growing business (traction) 2) been accepted into a "top school" (pedigree)
It's not a conspiracy per se, it's just a result of rampant cronyism and nepotism. How do you think investors get their jobs after all...
Some notable examples of non-rich founders, that the rest of us can hope to emulate: Steve Jobs, John Carmack, Palmer Luckey, Linus Torvalds, Larry Ellison.