Even if "it" did exist, its very nature would preclude procreation and the passage of the carrier's genes. It could therefore only be a randomly occurring, unique genetic phenomenon of single-generation duration (per "carrier") - which is essentially a mutation. If it's genetic, it would be an anomaly. And genetic anomalies die off. Quickly.
So, maybe it's something else. Like Mommy/Daddy issues? Recruitment by a "Funny Uncle"? Middle School Gym Teacher (ladies, you all know who I'm talking about)? Low sales resistance, maybe? Whatever. Even after years of sitting on a therapist's couch trying to figure out why they are so profoundly unhappy with the rest of their lives, they refuse to even consider that maybe the fundamental basis of their identity might just be a psychological disorder. Because then that would make them admit that they are, like the rest of us, flawed beings. Self-awareness....??? Nope....can't have any of that. It just gets in the way of that spiraling hedonistic rush to self-destruction.
That usually either shuts them up, causes them to try to deflect the discussion to some ridiculous "homophobe" strawman (doesn't work on me - I don't fear 'em, I just don't particularly care about 'em), or enrages them (which is usually pretty amusing to watch).
I ask them before we get into the debate so they do not know where I will come from and then say well if you believe in Nature and Darwin then surely we are here to reproduce to keep our species going and alive for another generation and with that why didn’t nature make it so for homosexuals to reproduce.
Isn’t that the an unnatural act
the usual answer is dur dur dur and then go off on the talking points with no direct answer to what I have said