The trouble is physicists who work in foundational QM who still utters phrases like "But the vista of all these parallel histories is deeply unsettling, and like many other physicists I would prefer a single history." and then they get dragged down into complicated alternative frameworks instead of the simple one they don't like. Einstein wasn't and will not be the only one to go down that path.

Over and over again it has been shown you need to calculate all the possible histories to arrive at the probability of a specific history to be realized. And if you need to calculate those histories to match the universe, chances are high the universe as well has to calculate them.