Li Shenron
Legend
With a strict definition, regularly.
With a loose definition, always.
With a loose definition, always.
I want one.
The economy of D&D makes no sense, and I blame dungeons for it. In my world, dungeons are very much explicitly inspired by ARPG video games like diablo; even if I myself still design them by hand, the intent is for them to feel randomly generated with a mish-mash of creatures and no cohesive culture in them. That's because the dungeons in my setting are basically the backrooms and maintenance tunnels of the Gods; they're not "for" you, they keep physical reality running in the way you've become accustomed. That hunk of adamantine you pulled out of a mural? That was actually a mystical circuit board and thanks to you now there's no enchantment stopping typhoons from flooding an archipelago, you just killed millions.
I can't say I came up with it, I feel I've played so many video games with this "twist" (EDIT: I think my biggest influence were the Engwithans of Pillars of Eternity, which is also just an amazing setting that you can and should use for your D&D games). For my setting explicitly, the planet it is set on underwent partial terraforming, the "gods" are actually humans back on Earth in an otherwise hard sci-fi setting that don't know magic exists... but these humans don't have FTL communication so it took thousands of years for them to send probes to terraform the planet and it'll take thousands of years for them to find out not only did it fail, but also somehow their technology malfunctioned and ended up cloning dinosaurs with wings that breathe fire. My setting does that Numenera thing where people don't really differentiate between high tech and magic.That's probably the most logical explanation for traditional dungeons I've ever heard.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.