I don't mind XYZ sexuals having sex, I never cared for the whole degeneracy or hedonism angle.
Considering it still looks like the genetic explanation is the best bet, they are mostly just born differend. Transsexuals seem like manipulative scum an extraordinary amount of the time, but that might just be high IQ, autogynopilic autists as a subgroup. Gays are overly into young boys, but men generally are into young partners, so maybe they are just less hesitant in pursuing their desires because they know they won't be judged the same way straight men would be.
I have lived most of my life chasing any crumb of pleasure and joy I could get my hands on. I wouldn't consider myself a hedonist, but utility is just a bit more refined of a term for the same idea and overall goal, more feeling good, less feeling bad, with hedonism also being more unapologetically self-centered. Pleasure isn't worth much without some sense of meaning and purpose ,and pure hedonism doesn't offer that, especially if you are a KHHV not getting any real pleasure and are stuck coping with video games and porn.