In a historical book or textbook no. In an official publication of an RPG yes.
The latter is a game and one that affords the opportunity for players to play explicitly evil characters. You can present canabalism, eugenics and slavery and the Sorcerer Kings as explicitly evil, yet players in D&D can play "on that side".
Further it is not just those objectively morally rehensible topics that are problems with dark sun, it is also the underlying messages on religion (aetheism causes society to fall) and the environment (people in power ruin the planet) that are a problem as well for a company trying to appeal to a large audience. Playing to opposite sides of the spectrum on these themes virtually assures you are going to piss off a lot of people with what will be interpreted as thinly veiled support for conservative and liberal extremist ideals respectively.
Then there is the sexism, both in the plot lines and the art. Playing a 5E Darksun reboot recently I commented that my PC was apparently the only woman on Athas that is not a stripper in her off time.
No if you eliminate all these things - slavery, eugenics, canabalism, apparant links to modern day political dogma and sexist plot and art ..... is what you are left with still Darksun? Probably not.
I'm not sure that they would need to get rid of the environmental message. They
could alter it so that it's less "people in charge" and more just as a byproduct of magic, and say that even common folk using magic caused harm, but... I'm not sure that they
need to. Or should. This one is actually kind of important.
They can "get rid of slavery" by having it as a uniform evil,
not something that the PCs can or should be involved in. I can't remember if they included prices for slaves in the original books, but right-out saying "PCs can't buy or sell slaves" would help (or potentially, good or neutral PCs can't buy or sell slaves). In addition, there could be a section on running DS with or without slavery, depending on what the table feels comfortable with.
I'm not 100% on what you mean by eugenics. The old MCs had numerous monsters that were created by the sorcerer-kings, which isn't all that much different from all the monsters that have historically been created by insane wizards. Just remove the idea, if it existed (I can't remember) that they were
bred from the books. The DM can imagine they were grown in a vat if they wanted. Heck, there can even be art of some monster being grown in a vat. If you mean Muls, that's fairly easy--their birth isn't so abnormally dangerous to the mother as to be noteworthy, and most are born from consenting parents rather than bred for gladiatorial fighting.
Speaking of which, they can take stuff from actual Roman gladiators and run with it. In ancient Rome, they were slaves, but semi-celebrities, often literate (at least enough that there's gladiator graffiti), there were rules, and I've seen reports that they may have been at least a little bit staged (at least in fights that weren't supposed to be to the death). Dark Sun gladiators can push that to 11 and go complete WWE.
As for cannibalism, what they can do is move away from the cartoonish "savages putting people in cooking pots" and make cannibalism have societal and religious significance, like it does in some actual cultures.