Would you mind specifying exactly what kind of “gay sex” might spread this - or any other disease - that does not equally apply to heterosexual anal or oral sex?
You cannot elevate protected groups above criticism. That's a dangerous privilege and as we see in this instance, condoning this sort of irresponsible behavior puts greater society at risk. Straight people on average are not having nearly as much anonymous sex with nearly as many partners and, ergo, not spreading nearly as much disease.
It's probably a manifestation of sexual dimorphism. The average woman is not as willing to sleep with a stranger. Not sure about how much lesbians get around though.
0. https://carm.org/homosexuality/statistics-on-sexual-promiscu...
Backup your stuff