Magical realm

Where the 4chan culture intersects with human-directed gaming, you will read discussions about That DM. One such is the /d/M. He's the moral pervert, who brings his "magical realm" to his players.

This isn't new in fantastic fiction. I am aware of several Magical Realms in various Arabic / Islamic collections, which the Arabs really shouldn't have copied, as the Muslims themselves mostly agreed... but the stories got copied anyway. I'm unsure on who was the first author to parody that some people's fantasies are best left to themselves. Being among the English speaking peoples myself I'd go with William Shakespeare in The Tempest. The /d/M is usually stupid enough to play the magical realm straight, although some have just enough self-awareness to bury it like Forbidden Planet did ("I'm not the preevert, the VILLAIN is the preevert!").

I am not here to praise Gary Gygax. I am also not here to bury the man. As I look at Gygax-written modules - B2, T1, G1-3, S1-2, S4, WG4 - I don't find magical-realming. I find squalor and/or horror, among the bad guys; but there's an authorial distance. His colleagues in 1970s / 80s didn't squick me out, either, for all the Satanic Panic at the time. Some scenes in the Slavers series veer to BDSM maybe but that's why they hired Moldvay.

So now: let's talk the Drow series, D1-3 culminating in the Vault of the Drow. The dark elves are a matriarchy, by decision of a demoness, who has lent her [spidery] powers to her priestesses. This is a world of silk, nets, and whips. Kinky!

I think that your characters might run away from you, if they are Chaotic Evil. The hyena-humanoids, the gnolls, are sometimes played as a matriarchy but they're brutes; you can run them as ogre-men without Y chromosomes. Not so the drow. Their evil is a truly feminine evil. We own sufficient literotica by women to tell us what their kinks are like, if they are but given perfect freedom. (And in-house Jean Wells was writing module B3 which magical-realmed Gulluvia, thankfully not carried forward when Moldvay parachuted in to save that module.)

As I look at module D1, not a Magical Realm itself, which I hold as an unfinished project right to the Queen of Spiders 1986 end: I see Gary Gygax and his colleagues not wanting to go further into the ghoul territories (certainly also the vampires' territory). Here are creatures who procreate horizontally, by infection.

The illithids were a problem from a narrative perspective, I think a full mistake. The ghouls were a problem from a moral perspective. A good DM could handle this. Some are /d/Ms and you don't want into their realm. Those DMs who are plot-focused just won't want the headache. I assume Gygax for the latter.