As a person who has watched this kind of thing happen a lot: I think a lot. I had a bunch of friends on tumblr who wrote and exchanged very similar fiction and art. The ones who were known to be trans, female, enbies, or non-white got harassed a lot. The one who was understood to be a white cis male got left alone. And this is on tumblr, where the ostensible position of a large part of the user base is that white cis males are Bad People by default...

So yeah, pretty sure it's that. I almost never get harassed by people who think I'm cis male, the bulk of the harassment came from people who thought I was transmasc.

Probably the furry stuff too, which is honestly sort of terrifying, do these people not know how much infrastructure relies on stressed and overworked furries?

You obviously don't need anyone to tell you this, but for passersby for whom this has not been on their radar before: this is almost certainly true. HN commenters will on occasion be superior jerks towards anybody, but this is some loud posters' instantaneously adopted position when they see a name that doesn't code as male--for another example, see many `rachelbythebay.com` posts, where you have randos getting sniffy and assuming she's incompetent or junior for some Real Interesting Reasons.

By my estimation it is real, the proprietorship (who I like and appreciate personally, and I think are operating on good faith) of this community has often made noises about how it should be better. It's not, and it should be.