[...] But the mechanics .... hmmm. Even completely aside from the whole elephant-in-the-room issue of psionics, Dark Sun was explicitly written as a low-magic world, even in the context of a much lower-magic edition of D&D. It's hard to write a setting where arcane casters have to conceal their existence from angry mobs for an edition in which even 2/3 of barbarian subclasses have flashy magical abilities, at-will cantrips are all over the place, and the term 'arcane' no longer has any real meaning. It's hard to have a survivalist, water-lacking setting in an edition where wilderness survival is pretty much trivial and 'create water' is a widely accessible first level spell. It's hard to have specialised elemental clerics in a system where the existing clerical spell list contains spells of all elements, and there's no mechanism analogous to the 2e 'sphere' system for restricting that. Sure, you could throw back to 2e products like Domains of Dread and go through the spell list line by line and explain 'spell X produces 1/10 of the listed water' and 'spell Y is not available to air, fire, or earth clerics', but there is absolutely no way that WotC is going to spend a bunch of pages doing tedious paperwork like that, especially as the page count in their products seems to be shrinking year on year as it is.
Dark Sun is a setting about hard limits, about restricted choices and restricted resources. Limited magic, limited water, limited metal, limited freedom, limited options. This jibes extremely poorly with broader design philosophy of 5th ed. And no, this isn't a rant about how 5e players are spoiled and soft and lazy and dumb and all these kids should get off my lawn. I LIKE 5e. I have my issues with it, but on the whole it's probably my favourite edition. But as a system for telling the sort of stories that Dark Sun was designed for? It's not an easy fit. You either have to spend a load of page count rewriting the system to fit the setting, or you have to deal with a bunch of PCs whose capabilities just flat-out contradict a lot of the basic setting assumptions.
