What was different about the Israelites was that their constitution separated them from other peoples. Israel was establishing their identity. They were few but they also consisted of all walks of life; representative of all mankind. They needed a separate and holy identity. They had one g-d and it was to be representative of the Creator.
Medical examples are a poor and useless comparison where homosexuality is concerned. Homosexuality is not a disease.
In other words, obeying the interdictions on these sexual practices were a means by which a people could signify their membership in a holy congregation, order or community separate from the unholy and heathen people around them. It would be similar to taking vows in a religious or monastic order or some such, where the internal rules would have no implications for those people who are not initiates in that order.
-You just don't get it. Go back and read over my comments that you don't get it.
Did I get it?
I can accept that. There would not be the same moral obligations and constraints on those outside the order, nor expectations that they abide by these. This is why Christians do not feel obligated to abide by the requirements of Judaism. Christians are members of another order with their own internal rules. However, the implications for those not within this holy congregation would ultimately be eternal damnation, which is what Christians continue to warn people of. So, it would behoove people to seek entry into this order, if this is truly the case.
But. actually that interpretation is just another iteration of moral relativism. God, surely, has universal standards of morality, and this would certainly include an interdiction on homosexual behavior.