I prefer the settings where the existence of the gods is fact (Forgotten Realms, Exandria). I'm big on afterlife stuff (tell me where the souls go!). In FR, nay-theists would probably get Walled, but in Exandria (from my understanding), nay-theists may be more common, and there isn't a punishment for them--at least as long as they were otherwise decent people. I think souls go to the appropriate god/plane.
Personally (and I may get some flak for this), playing a non-theist cleric or paladin should be a setting-based option. It works for settings like Eberron, but less so for settings like Forgotten Realms, so I don't think it should be an "all-settings" option. People seem to get bent out of shape over deities, when they're fine with every other fantastical thing in D&D. Why can't there be gods, and thus clerics and paladins who receive spells from them? I'm not particularly religious irl, but that doesn't mean I don't enjoy deities in fantasy worlds. Indeed, I think they enrich the world.
It's a one off tweet that didn't get a lot of engagement, but it might be an indication that the Wall might not be a thing going forward.
This particularly Tweet may not have gotten much attention, but an errata from the
Sword Coast Adventurer's Guide did. The paragraph on the afterlife originally contained a single sentence mentioning the Wall, but that has been omitted. This caused several discussions in FR circles. So far, it's just an omission, and there hasn't been any further explanation.