"In order to bake an apple pie from scratch, you first have to create the universe"

If you don't create the universe, then you aren't really making an apple pie from scratch. In the same way, what you're referring to doesn't simulate the universe - not in the way that it is simulated in the simulacrum hypothesis.

In the simulacrum hypothesis, the entire universe is simulated. You exist entirely inside the simulation rather than being merely plugged into it, and so do I and so does every other consciousness that exists.