Again, the attempts to rewrite biblical morality leave me unconvinced, largely because of this background. To argue that we know more about sexuality than they did is a bit hard to take when you actually dig into the Greco-Roman history. By the way, William Loader, who probably knows more about ancient sexuality than anyone alive, agrees that the Bible is unequivocally against any kind of sex outside of heterosexual monogamous marriage. But he just says that the Bible is wrong.
He's an honest man. You can't have it both ways. Either you agree that scripture is correct or you agree with Loader that scripture is wrong. You can't claim scripture is correct by reinterpreting it on this issue.