You made such an informative Dragon Talk on planes and worlds, explaining how assumptions changed between editions and everything, no sarcasm here, and now we have a book that doesn't fit the 5e mold because it is based on M:tG. Not the end of the world, but a bit annoying.

— Millstone85 (@Stonemill1985) February 1, 2019

I'm curious how you think Ravnica doesn't fit the mold.

— Jeremy Crawford (@JeremyECrawford) February 1, 2019

… If I remember the interview correctly, you said that early D&D assumed all its campaign settings to be part of the same cosmos. Then there was a time when D&D moved away from that concept and, for example, Eberron was designed as its own separate work of fiction. But now…5e is going back to the original idea of a shared cosmos, and you even talked with Keith Baker about a way to reconcile the Orrery with the Great Wheel. The result, you said, was a story about the Progenitors wanting a world of their own, with its own planes, and managing…

— Millstone85 (@Stonemill1985) February 1, 2019

… a similar story for it? Or should it simply be regarded as a part of the M:tG cosmos, now presented under the 5e D&D ruleset, but unrelated to 5e D&D lore?

… to shield their creation from the larger cosmos. At a DM’s discretion, that shield could finally break under the pressure, starting a “gold rush” for beings of the Great Wheel, such as devils from the Nine Hells. I really liked that idea.

But what about Ravnica? Is there… That's how I think it doesn't fit the mold. But don't get me wrong, GGtR is a great book.

— Millstone85 (@Stonemill1985) February 1, 2019

Pathways between multiverses exist in D&D. For an example of people traveling from one multiverse to another, check out the Acquisitions Incorporated sessions I've DMed. The characters go from the Forgotten Realms to Ravnica and meet an NPC, Vi, who travels between those worlds.

— Jeremy Crawford (@JeremyECrawford) February 1, 2019