I think D&D needs to do at least big "political drama* setting and one real War of the Pantheons setting.
By political drama, I mean kings, lords, and government. Have more concrete feels to the powerful NPCs and tie in the idea that adventurers are doing the work nobles can't or won't do with their power or are using the adventurers as cheap labor to clear out monsters for development.
For War of the Pantheons, D&D should really have a setting where the religious warfare is hot on the cosmic end. No more of this God X hates God Y and Archdemon W but all they do is sic a dozen clerics, druids, paladins, and warlocks at each other scattered across 4 continents, 3 planes, and 1 sea so no one sees the fighting. No man. NotOdin should call out NotZeus for the mantle of Sky God and march human, dwarven, and drow berserkers down to smash some human, satyr, and orc hoplites. A setting where player characters have some real race, class, party, and personality restrictions and players support crusades because the dungeon is in enemy territory.
As D&D moves to the idea that you can build the PC you want, it should support settings that shine bright lights on the advantages and disadvantages of how your characters are made and how they act codified in rules and lore players fully know when they step into the setting.