Totally, hence we see startups from the U of Calgary and the Missouri School of Science & Technology. Thankfully we're in a world where amazing founder can come from anywhere.
It definitely matters, but our point was that it's not an impenetrable barrier. Stanford/Harvard are still highly represented, but so are some lesser known state schools.
Im a bit skeptical that school doesnt matter - but I'd agree with you completely if more founders came from my school, ha-ha.