You’re thinking in terms of how we do simulations within our universe. If the universe is a simulation then the machine that is simulating it is necessarily outside of the known universe. We can’t know for sure that it has to play by the same rules of physics or even of logic and reasoning as a machine within our universe. Maybe in the upper echelon universe computers don’t need power, or they have infinite time for calculations for reasons beyond our understanding.
For software and devices running locally, sure. Much of what MS does these days is cloud based where the bulk of the electricity is being used in a data center somewhere and the customer isn’t (directly) paying for it.