"And if they’re really strategic older founders hire engineers in their 20′s and 30′s who don’t know what they’ve been asked to do is impossible (exactly the strategy of my partner Ben at E.piphany.)"
That sounds a lot like age discrimination to me. He should be careful saying things like that, because it's illegal to hire based on age in the US.
He's probably advocating that for the same reason that EA and Amazon prefer junior developers: they're more willing to tolerate being treated like slaves than seniors.
I think the fairly widespread use of interns is the de facto way of doing age-based hiring, without it officially being age-based hiring. Any company that tries to recruit from college campuses is, at least in part, doing age-based hiring.
That sounds a lot like age discrimination to me. He should be careful saying things like that, because it's illegal to hire based on age in the US.