I agree with this completely. PG basically said that the reason there are not many females in YC is that not that many qualified females apply. The interviewer then asked "what would be lost" if YC either lowered their standards for female applicants, or did more to encourage qualified females to apply. And PG basically (and perhaps unintentionally) dodged the question, and reiterated that there aren't as many qualified female applicants as male ones, because in some sense YC's 'ideal' candidate is a twenty-something who's been hacking for 10+ years, and more of those are male than female.
I'm not saying that PG is necessarily sexist or a bad person for saying all of this. But he did basically say that there aren't a lot of twenty-something females who have been hacking for 10+ years. And then he seems to sort of back away from that statement in "What I Didn't Say". In the original interview, he said "We can't make [these] women look at the world through hacker eyes and start Facebook because they haven't been hacking for the past 10 years." In "What I Didn't Say" he says "When I saw [the above quote] myself I wasn't sure what I was even supposed to be saying. That women aren't hackers? That they can't be taught to be hackers? Either one seems ridiculous." Basically, he was saying a less-crazy version of the first statement. Namely, that there aren't that many 20-something female hackers.
In summary, it seems like PG stated an inconvenient and perhaps unfortunate truth (and implicitly declined to get into what he could perhaps do to make this truth untrue), The Information reported it in a responsible way, and then ValleyWag re-reported it in a misleading and sensationalistic way. And then PG somewhat disingenuously claimed that he didn't say what he actually said.
Also, the irony is rich that all of this involves the guy that wrote "What You Can't Say".