India, which has the worlds largest concentration of Hindu's outlawed aspects of the caste system in its Constitution because of the efforts of Gandhi, a Hindu. One reason Christians are persecuted in India is because they are making inroads with the Untouchables. The caste systems, in my view seems and is horrible because I was raised in a culture that believes that a person can better themselves through hard work and/or education. My parents taught us that all men are equal. My father put it this way: "All men are equal because all men put their pants on one leg at a time". So again your assumption is incorrect.
Now, the history of homosexuality is long and varied. Some Greek philosophers promoted the practice and others condemned it. Christianity was first spread in cultures that accepted pederasty, phallic worship, and recreational homosexuality. Many Christians are not aware of the fact the first person to opine that Genesis 19:5 is the reason for the destruction of Sodom and Gomorrah was Philo of Alexandria, a Hellenistic Jew in the 1st century BCE. The Biblical explanation is found in Ezekiel 16:49-50 and it had nothing to do with homosexuality.
Hinduism does not take a dogmatic stance on homosexuality, however what I found in my research is the consensus is that the existence of homosexuality was acknowledged but not approved.
Other cultures viewed male homosexuality as a gift of the gods. Most shamans were homosexuals. Some Native American tribes also viewed male homosexuality as a gift of the gods, however it was so uncommon that to appeal to these cultures as accepting homosexuality as a viable alternate lifestyle is incorrect.
Now, as to the "parable"; God does not destroy human beings who violate His design for mankind. If He did there would not be a human being on this planet. It is for this reason that the "parable" is not a "parable". God allows human beings to live their lives as they please.