I sorta feel like one problem with "Does D&D support X?" is that D&D is a pretty ambiguous term. Do we want to frame D&D from a strict RAW-only perspective, or from a Star Wars-like "this corporation determines canon", or more like Chess or Bridge where they evolve over time in a decentralized way, or more like Batman or Warrior Cats fandom? From the last two viewpoints (and arguably the second) there are plenty of places for support/structures to come from that's not the written/published rules.