You can explore how the simulation works, there's just some other layer you can't explore. Or maybe you can somehow.
When you look at the stars, are they real or a simulation in your brain? Does that mean you can't explore them?
This is unknowable.
That fits the definition of a simulation.
You can never really disprove that some malicious entity is just making you think you're seeing the stars and talking to people, if you want to go back to philosophy about it. There's a bit of assumed faith
I don't agree with this argument, but it circulates occasionally.
If you are in a sim, then the sim execution is an expensive process, it produces heat and consumes energy. If you are in reality, a material body, then keeping alive also consumes energy. The debates about consciousness often assume a cost-free regime, a platonic perspective. I think this is wrong. We have much to gain thinking about how a process provides its own energy, or how it balances costs and gains. Maybe we can find answers about consciousness too if we chase down the cost recursion path.
If simulation theory (or similar ideas) are real, it's entirely possible that the "real world" running the simulation operates on completely different physical laws than the simulation.
An engineer would ask what a simulation would simulate. This is the core of the meaning behind that word. And if the answer is reality and it hints to the fact you cannot perceive everything and you conscience tries to construct a cohesive understanding from limited perception, than I would dispute the fact. The only one who tries to do that are philosophers. Going back to my objective, not-simulated ignorance now.
Simulations are systems which have various rules built into them which govern (entirely) the behavior of the components of the system (at whatever levels the rules apply).
A given simulation may have rules that are believed or are intended to generate behavior within it which are similar to some other system (e.g. what we experience as "reality"). But it may just as well have an entirely different set of rules intended to create entirely different, even unknown and unpredictable, behaviors.
Any similarity between a given simulation and what we experience as reality is a property of that particular simulation. There is absolutely no reason why a simulation that is utterly different from our reality could not exist (and indeed, almost certainly already does).
A simulation does not have to model reality and multiple simulations trivially exist. But I don't see why that would imply anything for reality as well from that.