Some of my favorite shared universes of my younger years have been killed dead by corporate exploitation. When a shared universe becomes a brand and franchise, it is creatively dead.
Star Trek--dead since Picard. Really since Discovery, which was obviously inspired by the fan film, "Axanar."
Marvel--dead, and beaten into the ground since "Endgame." Black Panther, and Ms. Marvel was fun... and that's about it.
Star Wars--mostly dead since the Disney takeover, except Andor and the Filoniverse.