For this to all be a simulation, there must be some sort of software running, perfectly, without experiencing any errors, for an extended period of time.
This is, to put it mildly, impossible. There are a theoretical infinite number of edge cases to account for, and there's just no way software could be written to account for all of those. The source code would take up more space than all the atoms in the entire universe.
All of that aside, this is my least favorite thing to speculate about. Even if it is true, which we have basically no way to confirm - it's like asking for proof a deity exists, but even if we can prove it's true, which we can't, what do we then do with that information?