I do think part of the increase in HSTS's is that gay culture is so specific nowadays; all hookups, BDSM, gay clubs, sex saunas, rainbows, pride parades, heavily defined lingo, etc. If you were a young gay man who just wanted a regular relationship and didn't have any fetishes I could see how being a gay man would be offputting and foreign. Imagine seeing all your female friends with their normie long-term boyfriends and all you have available is gross Grindr guys who just want to fuck. With transitioning they think they have the chance to get normal men. Doesn't help that HSTS's have the lowest IQ so they think it'll work out.