Thing is 5e is chockablock with flavour elements that either directly contradict or at least never appeared in earlier editions. And this was perfectly okay. Adding in the Weave to all D&D worlds is considered perfectly fine, despite it being every bit as restrictive as tying Far Realms to psionics. Even in Dark Sun, we have The Weave, apparently. ALL magic in D&D, at least according to the books, comes from The Weave.
This flatly contradicts most settings and is a complete departure from earlier continuity. Yet, it passes without comment. So, "It must fit with prior continuity" is a ship that sailed a couple of years ago.
You don't get to pick and choose here. "Oh, it's okay to change that continuity because I don't care, but, don't change this continuity because it's important to me" is, to me, frankly hilarious. Pretty much par for the course, IMO, but, still something I find endlessly amusing.
Sorry, but, if you wanted continuity to be an issue in 5e, you should have been stepping up to the plate a couple of years ago. Now? Now, it's just self serving. So, why should i care? No one gave a toss two years ago when the 5e books rewrote virtually every aspect of continuity - monster flavour, class flavour (any alignment paladins that aren't tied to a specific deity or faith?), setting flavour. On and on. 5e changed continuity easily as much as 4e did but, they did it in such a way that instead of people recoiling, they fell over themselves to pat WotC on the back. Well, the bed's been made. Good luck on stuffing this particular genie back in the bottle.