It stinks of Blizzard talking out of both sides of their mouth to commit to an inclusive office space but to then drop the incubus model, which is actually wearing less than the succubus model. I mean, I think it’s dumb, and I’d appreciate it if Blizzard gave warlocks customization options for their suck busses, but I can understand why the incubi makes people uncomfortable. Remember, even the succubus was deemed too family unfriendly to the point that Hearthstone removed them from the game.
Most demons do not have an explicit sexual identity. They’re demons, they were not created through tradition procreation. Sayaad in particular could be considered emotion-driven vampires . They feast on the emotions of their victims. Much of Azeroth is sexually repressed, so it makes perfect sense that they lean into that when they could just as easily get their fill from sadism or grief and misery. New Sayaad are created when a Sayaad has cosumed so much of their host’s spirit that it can only function by doing the same to someone else. Which is why Succubi and Incubi rarely have offspring- they have a near-endless life cycle, siring a new Sayaad means a new mouth to feed, and in the cases where they are genuinely in love with their host, that transformation changes them, so crossing that line carries serious considerations.
It’s also why they tend to shun night elf society- a matriarchal society isolated from the world for 10,000 years and which had the overwhelming majority of it’s male population take a nap in the Emerald Dream in that time would actually develop into a fairly sexually open society. This is also why Sylvanas burned Teldrassil- she was massively envious of just how far ahead Night Elf society was in that respect where her loving a human, despite it being the most prominent feature of the Windrunner family line, would have been seen as unbelievably scandalous by High Elf society.
And before you say it, my interpretation is as good as any other and it at least attempts to explain the lore within the context of Warcraft itself rather than appealing to the sensibilities of it’s author.