humble minion
Legend
Lukewarm take - D&D shouldn't have a cosmology. Cosmology should be setting-specific. FR - a very pantheon-heavy setting - should have its array of divine domains where the deities reside. Spelljammer shouldn't have a cosmology because it's 100% about astral sailing to an infinite variety of weird otherworlds rather than plane-shifting there. Dark Sun shouldn't have any cosmology that allows you to escape Athas (or import water or metal etc from Sigil or the elemental plane of water or somewhere) - Dark Sun stories are about survival with limited resources and options, and the Black and the Grey support this sort of story with a spare, stark cosmology for a spare, stark setting. Campaigns in Krynn should hardly even think about extraplanar matters at all, unless in the final climactic session you're actually riding your dragon into the Abyss and sticking your Dragonlance in Takhisis's face.
Cosmology should support the sort of story a setting intends to tell, and a Ravenloft story isn't a Strixhaven story isn't an Eberron story (Eberron got this right, btw). The whole multiplicity of elemental planes and the Great Wheel works fine for Planescape, and the Astral Sea for Spelljammer, but both of them are a terrible fit for Athas. The obsession with shoehorning all the campaign settings into a single cosmology damages all of them, AND makes the cosmology less coherent in the bargain.
Cosmology should support the sort of story a setting intends to tell, and a Ravenloft story isn't a Strixhaven story isn't an Eberron story (Eberron got this right, btw). The whole multiplicity of elemental planes and the Great Wheel works fine for Planescape, and the Astral Sea for Spelljammer, but both of them are a terrible fit for Athas. The obsession with shoehorning all the campaign settings into a single cosmology damages all of them, AND makes the cosmology less coherent in the bargain.