I'm just mentioning homosexuality since it's one of the most obvious lifestyles to illustrate what societal control looks like (in our world). I only mention in the context of the Qunari because they inflict that type of control on EVERYONE. They make everyone feel like gay people do in our own world. The extensive role designations frighten me on that level. The closest we have to it now is Sharia law. So it's hard to have "fun" with. I can roleplay just about anything else. I'd rather be a Dwarf nug humper than this.
I don't think Sharia law means what you think it means. Or at least, it certainly doesn't mean to people who practice it what you feel it means. The Hijab, that veil that is to many in the west a symbol of the enslavement and objectification of women, is to many who wear it a sign of respect and consideration to not be an object of lust. A number of practices we think of as oppressive, they think of as respectful and protective. In Afghanistan, for example, it is very bad manners to look at and address the host's female relatives unless invited to: this isn't because women have no value, but rather that women are respected and that by not looking at them unless invited you are making a point that you aren't oogling a man's wife or children. Similarly, the prohibition about women traveling long distances alone without a male relative originated in a time when bandits and packs of feral dogs were a much more common problem and travel by one's self was dangerous.
To modern western sensibilties, Sharia means oppressive and unreasonably restrictive. To people in highly corrupt and poor societies with non-functioning justice systems, Sharia is a sensible and appropriate moral system that, by living by, you would live a good life.
Touching back to your original question about how a gay person could write the Qunari? I think the element of distinction would be a lack of distinction. Homosexuality is a particularly hard taboo because it is particularly exclusionary. Everyone has sexual and romantic desires, but yours are condemned. When you remove the exclusionary aspect, when everyone bears a burden, it can often be far less oppressive and stigmatizing to an individual.