I have similar questions about the apparent over-representation of LGBT people among high-profile software developers, but it feels like it's never okay to ask those questions.
My own explanation is that to be good at computer science you need to have had spent a lot of time in front of a computer during your childhood. The LGBT community used to be much less (and still is in most places) accepted IRL, and as such you'd have to find your community online.
So here you have it, that's my theory, a lot of LGBTs spent a lot of time online and then got hooked on computer science stuff.
I'm gay and many of my legit LGBT friends have noticed a trend where lots of younger folks are claiming to be queer, bi, non-binary, asexual, pansexual, trans, etc., without a lot of evidence that they're anything other than a straight person looking to feel special.
Same thing on Mastodon, which I tried for a month or so. It seems every single profile you open some of the claims you mention are there, followed by disabled, and a bunch of (self-diagnosed?) mental illnesses.
It's like they're collecting pokemons. And it's not used as a list of characteristics, it's their "identity" and an accomplishment. It is center to every single thing they say, whom they associate with, etc.
One possible factor is that GSRMs are still widely persecuted and thus are not inclined to be "out of the closet" about it. That's also why people can get a bit defensive about asking questions; enough people ask such questions in bad faith that it makes it hard to identify when someone's asking in good faith.
So here you have it, that's my theory, a lot of LGBTs spent a lot of time online and then got hooked on computer science stuff.