This argument is underwhelming to me. Physicists found that simulating a few hundred electrons (using one particular method) would require more atoms than there

This argument is underwhelming to me. Physicists found that simulating a few hundred electrons (using one particular method) would require more atoms than there are in the (known) universe. This is a good argument that we cannot simulate our own universe precisely, but it says nothing about the underlying nature of reality. Consider if Pacman took some time to study physics. He analyzes Ghost behavior and realizes it would take more than 255 levels worth of data to describe it. Pacman concludes that he must not be in a simulation, because clearly there are only 255 levels in the world.