Okay, I’m having a hard time parsing that; some of your phrasing is awkward (“suitably grim justifying mythology”) and you’re using a lot of technical language, but let me see if I got it.
Yes, I know, pot, kettle, etc.
Are you saying that straight guys/gals have a sexual incentive to establish some kind of social rules, either formal or informal, to deal with the opposite gender? And that, absent that incentive, gay folks can trend towards a more gender-insulated and less diverse community, which can lead to discrimination and bigotry against people outside of that community?
If that’s not what you’re trying to say, I’m having a hard time reading it (and I’m feeling a sudden empathy for people who have to read my own writing). If I got it wrong, can you please simplify your language for those of us without a background in sociology?
(ETA: I’ve already edited this once, and I still think it has a bit of a hostile tone, and I can’t figure out how to fix that. Please be assured: I feel no hostility towards you or what you posted; I honestly am simply curious to know if I’ve interpreted your point correctly.)