That thread was moderated. You can tell because the founder’s opening introduction was pinned above dang pinning his own comment about a related thread. Those are conscious moderator actions which are about as transparent as it gets and illuminate the thinking on the other side (hint: you’re not aligned, but it sounds like you already expected that)
Also dang did that to the other big Show HN story yesterday: "Show HN: I'm 48 and finally learning how to be a game developer" so it seems to be a new thing he does independently of if the post is by a YC company or not.