So again with the crazy control freak?
I get that you aren't accusing everyone, but going from no elves to DM acting as supreme ruler is not a justified leap.
Ultimately most races that are not allowed comes down to personal preference. Or maybe it's just misdirection because of some secret that will be revealed later.
Other than the "hail Caesar," I only quoted what actual people in this thread have made statements about. (Though that is hardly much of an exaggeration from explicit and sustained claims to "Ultimate Authority.") And, as with other things, being so reductive that all things are lumped under the singular category of "personal preference" is exactly what elides out the issue. We would do better by forking open "personal preference" and looking at the different flavors within.
For example, there is a difference between, "I don't permit half-orcs; I know their
modern telling doesn't include a lot of icky stuff, but that icky history is baggage I just don't want to deal with" and "I don't permit half-orcs; it's fundamentally uninteresting to play a strong green person with tusks." The former is reflective, and shows a concern for meaningful issues (and could be rooted in any of a variety of experiences). The latter is petty and judgmental. The former is personal preference for cognizable reasons, the latter is personal preference with implicit judgment
and nothing more.
Or, to use an example of my own, one of the
very few things I don't permit: Evil PCs. I
could say, "I don't permit Evil PCs; it's just an excuse to be a dick and I don't let that happen at my table." That's judgmental and petty though. I trust that my players truly could play Evil characters that weren't just excuses to be dickish, that were interesting and well-written, if they wished to. The problem instead is that I know
I can't write good scenarios for evil protagonists. I'm far from perfect as a DM, but my players hare happy with the job I do. I could not produce the quality I do if I had to write for a world going to hell because the PCs are sending it there, and what I have already written provides far too much incentive for even "reasonable" Evil (e.g. actually-rational Lawful Evil types) to join with one or more of the bad-guy factions, guaranteeing a party split that the game couldn't survive (I'm certainly not running two separate games for two one- or two-person parties.) This has literally nothing to do with passing judgment on anyone, nor is it motivated strictly by my personal distaste and nothing more; it is motivated by my frank admission that the
consequences of having Evil party members on the game I run--
any campaign, but especially this specific one--would be too great.
And this is a major part of why I said I see this as pretty different from the inclusion of a particular race, as opposed to a particular alignment. Races can quite easily be from off yonder, "beyond the horizon" as I put it previously. The impact can be very slight beyond the one playable character not meeting many of their own species very often. The impact of Evil PCs, though? That can never be escaped. It will apply to
every wicked antagonist,
every temptation,
every scenario. I can avoid or minimize the impact of a particular species existing in the world. I cannot avoid Evil PCs behaving in evil ways; it will be
forced upon the narrative at every turn, inherently, and must either be continuously defused (or diffused!) or continuously risked. One person having scaly skin or hooves or a bull's head is easy enough to account for and will often (though, as I've stated, not
always) have little more impact than some surprise or suspicion from NPCs, unless and until I am comfortable with having additional cultural and physiological relevance--something I can build up to slowly. Evil PCs? I'm going to have to account for that from top to bottom, with
every bad-guy faction not being a rational temptation to join,
every serious situation justifying why a person who values their own power/interests before all else would participate,
every situation where they disagree with the non-Evil PCs risking a permanent party rift.
The one is a relatively small insertion into worldbuilding. It really isn't the enormous work most characterize it as--especially since most DMs don't actually go to the work of building truly realistic (as in, actually-resembling-reality, not merely verisimilitudinous) cultures, they make single-species monocultures with Planet of Hats tropes that rely heavily on pre-existing literature to have more than the vaguest hints of culture present. Catering to a party with even
one Evil PC though? That's going to define the whole game, guaranteed, every time, no matter what options the DM does or doesn't allow. I'm not
capable of doing that. I sincerely respect those DMs who are, but it's just not something I can do. I can't just lean on literature, the problem element is
a player character not a nebulous behind-the-scenes thing I can assign details to very nearly at my leisure.
And note my initial statement about flavors, plural: there may be
yet other things reductively disappeared by condensing all motive down to "personal preference," and I cannot say in advance whether they are good, bad, or indifferent.