[skissane]

> homosexuality (in males at least)

In many traditional societies, there is strong social pressure for marriage and children, arranged and semi-arranged marriages, etc - such that a person’s sexual orientation may not make much difference to their odds of heterosexually reproducing. Some people might enjoy heterosexual reproduction and others might endure it but they’ll do it all the same. So that would limit the selective pressure against genes that increase the likelihood of homosexuality

In the mainstream contemporary West, if heterosexual reproduction doesn’t appeal to you, then you just don’t do it-so selective pressure against those genes may exist to a degree that it formerly did not. On the other hand, the new possibilities for non-heterosexual reproduction (such as IVF, sperm/egg donation, surrogacy) might counteract that.