>>81685060 (OP)Gays are clearly people with a permanently gay type character build who were created by screwed up hormone levels in the womb.
Incest on the other hand isn't something anyone is built for. Anyone who fucks his sister or cousin could have just as easily just fucked a less closely related woman.
Trannies have less evidence supporting the idea they're the product of a special developmental problem with feminized brains, but gays have a lot of evidence for that in contrast. You can create gay male bottom mice in a lab pretty reliably with early on castration and hormone tinkering.