In short, while I think that overall 5e has done an amazing job of incorporating numerous diverse cultural cues and viewpoints, the one thing it is not so great at is allowing the "weird" exception. Something which has long been baked into D&D's DNA.
We may agree on very little, Snarf, but on this? I am 100% with you.
5e very much tries not to have, nor allow, the weird unless people jump through half a dozen hoops.
I will say, however, that one of the very things that made the "Gygaxian multiverse" start to have cracks and fissures...was Gygax himself. Not any of the (many, many) quotes you can find out there where he said something controversial, though! The issue was the
fixity of the Inner and Outer Planes. Whether Gygax intended it or not, things ossified (possibly even fossilized!) around this mechanistic, modernistic, "clean" classification.
And in that regard, I actually think 4e's World Axis was an effort to bring back some of the weird, without having to jettison the stuff people loved about the clockwork-universe model of the Great Wheel. That is, the World Axis more or less says that all of the various elemental planes, and the Abyss, and a whole bunch of other stuff besides,
all of that is somewhere in the super-infinite (no aleph terminology here!) Elemental Chaos, where the raw magic of STUFF is super strong. The same goes for the other five places. The Prime Material (which was often just called "The World" IIRC) could host any material plane, and even the great weirdness of Athas was presented as a very, very distant Prime Material where, from its perspective, either nobody won the Dawn War, or the Primordials did and then just sort of abandoned the world. The Feywild can cover every possible variation of Fairyland, from Annwn to Wonderland to Ys to Avalon to Tír na nÓg and many, many more. The Shadowfell can cover Dracula's castle, every place where hauntings impinge upon mortal affairs, Mirkwood, every graveyard where the wall between life and death is thin, etc. And the Astral Sea both absorbed many of the characteristics of the Ethereal, and put essentially every other "domain" plane, places dedicated to something specific or special, into its own little potentially-infinite pocket within the even-infinite-er Astral.
Point being, it re-integrated the idea that there could be
regular Worlds Beyond This One, while also keeping the "you can step under a bent yew and appear in Fairyland" element that made the rigid, defined planes compelling in the first place.
I think 5e could stand to bring back at least
that part of 4e, and it's part of why I was disappointed to see the Great Wheel return with such force, for lack of a better term. When the Great Wheel is understood to be just one cosmologist's
dream of a beautiful, perfect, symmetrical, consistent framework for a cosmos that resolutely refuses to be trapped in boxes like that (in other words, when the looseness of things
like the World Axis are allowed to be just as true, From A Certain Point Of View), we get to have our cake and eat it too. Odin gets to sacrifice himself
to himself, and yet still get the knowledge and power that result from the sacrifice.