"If you are with [progressive supes] then FU too" makes me wonder how employees, YC applicants, and others are treated if they are so aligned or appear to be. A laptop sticker or T-shirt with one of these names on it would be noticed, not to mention social media posts or "following" status.
YC portrays itself as a meritocracy and striving to find the right or the best founders. If the top officer is filled with such resentment, I don't see how that doesn't cloud the YC environment and the types of founders who are invited to participate.