Obryn
Hero
This was, like, a week ago, but I think this sums it up perfectly.The problem with this argument is whether adding new things to the setting (in terms of the PHB options) is "watering it down".
Settings grow and evolve, and sometimes they have to adjust to new material. Mystara in 2e had to find homes for multi-classing, rangers, bards, and half-elves. The 3e FRCS brought over all the planetouched races (previously from PS) to Faerun, as well as ret-conned the story. Arthaus Ravenloft had to contend with sorcerers, barbarians, monks, and half-orcs (the latter re-fluffed as Caliban). 3e Dragonlance did the same with Krynn as far as finding homes for sorcerers, monks, and such. 4e Eberron had to accommodate eladrin and dragonborn, 3e Dark Sun the psionic Handbook races, 4e Dark Sun a huge swath of PHB options like warlocks, bards, shaman, and sorcerers. Each of those settings were not ruined. They grew.
A few compromises can be reached (half-orcs were a poor fit for Ravenloft, so they replaced them with a mechanically similar yet thematically different race). But I think you'll see most, if not all, of the classes in PHB as well as a majority of the races have homes on Krynn, Athas, Cerelia, Mystara, Oerth, and Eberron. It makes sense to sell settings that can accommodate expansion. A DM who runs traditional Athas has little need for Volo's Guide to Monsters, so that is a sale lost. I can't see a scenario where having settings using half-or-less of the printed material out there makes them more money.
Having seen numerous campaign conversions over the past decades, I honestly think 4e Dark Sun was probably the best-handled of them (and the 4e FR was probably the worst).
The 4e DSCS kept what was core to the setting, and was judicious about its deletions and additions. And it went back in time to - probably - the best period for adventuring, right after the death of Kalak but before the whole rest of the Prism Pentad metaplot. So you have one 'free' city, and the rest of the setting is exactly what you'd expect.
It removed Divine classes. It could do that because of how 4e worked, in general, with its class roles. Yes, Dark Sun 2e had clerics. No, they were not "divine" casters. Solution? An elemental shaman subclass. A good, workable change within the rules framework, while preserving Dark Sun flavor.
Gnomes were removed, again in keeping with the original setting. But it added Tieflings and Eladrin. Tieflings are easy enough; there's plenty of room for more desert raiders on the sands of Athas. Eladrin could have been fumbled badly, but instead they were Dark-sun-ized; the "Feywild" - The Land Within the Wind - is a shattered, broken realm with mere pockets here and there, which you can enter into purely on accident. And the Eladrin are wizard-hating, fiercely secretive psionic warriors. A pretty neat edition, IMO. Dragonborn? I kept them out of the game until the party met Dregoth and his Dray; then they were available.
I ended up even having a Warforged - in this case a sentient golem of bone and obsidian - and it worked better than I had feared. (By this level, the whole sustenance/privation business wasn't an issue anymore.)
No, it's not identical to the 2e setting. But it was a mindful conversion and update, which is what I think is fair to expect from setting re-releases.