I've never been entirely sure why this debate matters.

A simulation, at least as we'd understand it, would mean some kind of set variables and set rules. It would be entirely deterministic, but you have to run it to see what happens.

That kind of sounds like…physics?

You have some basic elements like atoms and energy plus some set rules like conservation of mass, laws of thermodynamics, and the rest. Sure, we don't know what's going to happen next, but it does seem entirely determined.

Maybe I'm misunderstanding physics or the simulation hypothesis here. It's always seemed to me that we talk about a simulation as if it would be different than what we have now.