I'm confident players are not looking for the "dark ages reenactment of historical accuracy" any longer
Any longer?
Not trying to be a big downer, but they never were. There's no period in RPG history where that was a major, popular thing in RPGs.
The earliest RPGs are wargame-adjacent "kill your way through a deathtrap of a dungeon" deals. There was no "medieval sim" let alone "dark ages sim" component there.
Developing from that we get a kind of fantasy that is already rapidly trending towards high fantasy, Blackmoor and so on have a mix of S&S and high fantasy inspirations but that's still not "medieval sim" and Blackmoor, Greyhawk etc. were absolutely not "medieval" worlds, but rather very mixed in their level of tech, style of behaviour and so on. If you wanted to be a knight from a faux-European country that was an option, but just one of a buffet of options.
Dragonlance appears in 1984, and high/heroic fantasy in pretty much exactly the modern sense is here! And it's pretty much immediately a big hit. Not everyone is into it. People are still dungeon-crawling, hexcrawling, sandboxing, and so on, but this is something and people are increasingly realizing it as the '80s rave on. It is also at this period we get I think closest to the "dark ages reenactment of historical accuracy", except it's not dark ages, it's never dark ages (more's the pity!), it's solidly medieval. It's not 700 AD, it's 1100 AD or 1300 AD but for some reason all RPGs feel the need to be anachronistic and jumble together stuff even in ways the real would didn't and that don't make sense, so that limits the "sim". Still, we do get stuff kinda in that direction, like Rolemaster. And we get a subsection of D&D players going for that, but it's very much a subsection, because most D&D players are primarily pursuing something else.
So if this is all irrelevant lol I was very interested to think about the "any longer", because that's just never been major.
(EDIT - There is Runequest and that does present itself as 'dark ages' and claims them as a major inspiration, though in practice tends to seem - to me at least - a lot more the classical or ancient world just with solidly iron age equipment. And as much as it is an excellent game, it wasn't huge.)
A setting where Teifling for example are 'beloved and accepted across the multiverse' has lost the plot.
Is it any more far fetched than "English people rule the world and demand - and get - respect from pretty much everyone! And not just by force either!" when 1500+ years before they were* considered some of the dumbest hairiest smelliest stupidiest people on the planet?
I do not think that it is.
It might not be a plot you're you're interested it, but it's definitely not losing the plot. Like Cicero was saying the English, Britons, were so so stupid, so very very unhelp-ably stupid, they could never learn to read, ever. Just absolute failure of a race of people, not even good slave material, he advised his friends. Ugly, super-stupid, unreliable, nothing to recommend them. Caesar felt somewhat similarly, except his focus was on the belief Britons were profoundly unmusical, and could not sing nor play musical instruments.
< I am really working hard to resist the urge to put in an Austin Powers video here - I know he's fictional and played by a Canadian lol >
(PS you do not want to hear Cicero's detailed opinions about Jewish people, which he had, in abundance, suffice to say his views were more or less identical to what the most strident Islamophobes say about Muslims today. And I do mean almost identical. If you read it in a novel you'd think it was a very heavy-handed and on-the-nose analogy.)
On a more serious note you could probably do a pretty hilarious setting, good for at least a one-off campaign, where you did the 1800s but the British Empire was just orcs. Absolutely everything is the same, but we're orcs. Just behaving 100% exactly like 1800s British Empire people. Because honestly the way Cicero described Britons, we might as well have been D&D orcs or even goblins.
* = Hmmmmmmmm just saying maybe we still are?