I really want to believe it's because HN is extremely supportive of the trans community and therefore wants OP to be treated like most comments invoking a female perspective, by downvoting it.
Actually I should say "societies", because it's a highly international community, and these lines are drawn differently in different countries. Mainstream positions in one may be extreme in another. The same is true of regions within countries.
As for "libertarian bent" or other ideological biases, this is mostly in the eye of the beholder. We see just as many comments like, say, https://news.ycombinator.com/item?id=15307915.