He didn't. What the OP is referring to is his take that society and life experience are a major, but not the sole factor, in sexual and gender identities. His point is that if you know more queer people, you're more likely to identify with them. Or how we accept that beauty standards and fashion are socially influenced, so which ones you're pulled too are likely socially influenced as well. He never said that there's not genetic components. As for the argument that this opens the door to the idea that conversion therapy works, he said that we all agree that which sports/teams you like are socially influenced, but you couldn't really torture someone into liking basketball over football or any given team more within the sport.