I worked with a vietnamese guy (great friend) who was over 30 years old that told me honestly that he never heard of homosexuality until he came here. To be fair I told him that I was sure there were gays from his homeland, they just didn't make themselves known.
Not too long ago many Americans and most children in America wouldn't know what "gay" or homosexual was. It wasn't an issue because gays were few and far between and open gays for the most part didn't exist.
You certainly wouldn't see openly gay men prancing around on mainstream TV shows giving other men makeovers or taking positions of leadership. Whether rampant homosexuality is the symptom or a contributor to societal decay (or both) there is no doubt about the fact that where you find one, you'll find the other.
Now I should rephrase my statement to say - as you allude to - that in most cultures there is usually small minority of gay men (in or out of the closet) but in many you won't hear of it, so the societal pollution factor is irrelevant.
From my Vietnamese dictionary the noun for homosexual and homosexuality is expressed as follows in the Roman alpabet:
Nguoi dong tinh luyen ai - although that "string" of syllables lack the necessary diacritical marks above or below the vowels which tell the reader various inflections that need to be applied to the vowels.
That dong is in there is just a co-incidence.
Hand holding between friends of the same sex while walking in Viet-Nam is normal and doesn't mean they are homosexual. The reaction this elicited in new GI's was funny. This is a common custom in many countries.