If there’s another edition of D&D that has more settings and reskinned environments than fifth edition, I don’t know what it is. It’s a good game system; a nearly perfect balance of crunch and DM fait accompli. I don’t think it’s a universal system, and there are some suppositions baked into the game (like armor class and to a lesser extent, alignment) which is hard to square up in certain genres, like science fiction. Why people keep wanting to do space opera with d20 is a mystery to me in a world where we have Star Wars and Traveller, but I digress.