Because it’s not genetics lmao, it’s a mindset, just like religion
no it is not? Due to the non stop Lynch, fight and violence towards gay people and attacks on them almost everyone was afraid to come out ot tried to rationalize their thoughts and needs as if they were sick, that it's just a phase or that the other party is just tempting them even if they were not even aware that the first one had those thoughts. Families forcing young people to go on courses and camps to "out gay their kids" or even skipping that part and trying to do it themselves.
By that now, due to many protests for our rights, more and more people feel more comfortable to come out or are more eager to win with their families rights to be themselves since now, due to years of fighting for that, we have more and more right to speak up, even if it's still quite small to be fair.
it can be genetics, yes, but it's not like something passed from generations. It's just a natural thing that just sometimes appears.
Life is to experiment and experience, and you might have found your most comfortable combo of things, but others have their other ones or still seek them.