I want to make sure I got you correctly. Are you saying that the technical (co-)founder of the startup you're interviewing for on average doesn't know how to spot a good programmer?
No, I said to refer to items 1, 2, 3, 4, and 5. Nowhere did I say that.
If you really want me to get concrete, here's the dirt on startups hiring troubles: they usually flub 4 and/or 5.
Programmers are wising up. Only a small subset of startups are worth their time, unless it's a lifestyle choice, so they're choosy. Even among the small subset of startups that are worthwhile, they're not necessarily adept at communicating what actually appeals to programmers.