I think you are confusing modern record keeping, the advancement in heath care screenings and the detection of HIV. These modern abilities now document the explosion of gay deseses and activity that would have been lost in anyother age.
In the past homosexuals just died of these, and other self inflicted deasese.
There was no documentation the medical profession was young, if leaches did not cure you, then you died just like everybody else. How many homosexuals just went mad from syphilis? We will never know, maybe homosexual activity and promiscuity of heterosexuals was responsible for the spreading of all ancient plagues, we will never know, will we?