BOUNCING THIS THREAD
Two things prompt it. One is that my annual dose of gay culture (in another meaning of culture from Greenmanpp's in the o.p.) is coming up at the end of the month with the Dublin GAZE film festival.
The other is that I was looking at the findings about Ireland under the International Covenant on Economic, Social and Cultural Rights, and following links and points, ended up doing some searching to find our what 'cultural rights' means. That led me to this page at the UN's human rights site (which is a massive site!): http://tbinternet.ohchr.org/_layouts/treatybodyexternal/Download. etc ...
The document at that link makes clear that cultural rights include ways of life, rites, ceremonies, customs and traditions, etc., and not just the 'high culture' of the mainstream or dominant group in a society.
So it seems that culture in the meaning Greenmanpp asked about, in a broad way if not the specific examples he asked about, could be protected by international human rights law. However, there is nothing in the document I linked to about lgb communities' cultures, but equally nothing to exclude them. The way it is written suggests that what the committee had in mind was the likes of ethnic minorities or indigenous peoples.
So, what in our lgb cultures would be worth protecting?
Indeed, is gay culture a temporary phenomenon because we have had to come from criminality, through anti-dicrimination, to marriage equality, and is it something that will fade as a distinct 'identity' or culture in the next decades and century, and become as significant as being left-handed or red-haired?