I'm not sure how this is releveant; how can YCombinator influence this? The disparity in education has already taken full effect by the time people apply to YC.
It's great that YC has taken steps towards gender equality, but I don't think they have much of a say when it comes to inequality in education.
The selection problems that make Stanford grads have a leg up on startups isn't education related, really, it's network related. YC helps get more people into the circles required for fundraising. There's no other way I, for instance, would have had any credibility with the people who fund companies.
It's great that YC has taken steps towards gender equality, but I don't think they have much of a say when it comes to inequality in education.