In Chris Kalehiki’s video about leaving Blizzard he says one reason is he wants to design the real open world MMORPG you’re talking about. And he said this story is taking up too much air in the design space.
If the Devs like him who want to make a real MMORPG are leaving that means we will never see that kind of old school open world in WoW again. It will continue to be this style until Activision sees no value left in wow then it will discard the game.
The only way we see a return to form for WoW is if another company creates the kind of MMO we want and WoW suffers because of it. Until then it’s WoD 4.0. The only way back is for another company to beat Blizzard at the MMORPG game. Only then will their ears perk up, and they might attempt a real expansion. But I wouldn’t count on it.