It's not his first transphobic remark. Not only does he call trans people "traps", but he also objects to using proper pronouns because "I don't like my speech being dictated". It's easy to guess what he's obsessed with and ashamed about, and it's not about his lack of ability to treat people with respect.

https://news.ycombinator.com/item?id=15242499

And FYI, in case you're a nice enough person to have missed the reference, "Are Traps Gay" is an alt-right meme and shout-out to Milo Yiannopoulos.