Haha yes the most commonly used argument is (afaik) that if we could create a 'complete' virtual world, we would, and projects like this and how enthusiastic we are about it suggest that that's indeed the case.
(The argument then of course continues that if we would, our world's inhabitants would some day too, ad infinitum. Given such a stack, the chance that we're actually still in the top layer is very small.)
There is something nice in the sense that simulation appears to be completely unmonitored. If my Sims started producing scans that approximated the hardware of my Gaming PC, I would probably stop the sim... assuming I was closely monitoring.
Out of fear that they would come for me. I was not a kind God to these sims (under the impression they were toys), and their behaviours have shown me that though forgiveness is one of their capabilities, they do not wield it often.
My counterargument to this is that people simulating our world would be simulating all the bad stuff in it, which would be cruel and unethical. I think if humans were simulating us, they'd simulate a more utopian world. And if curious-but-indifferent aliens/robots simulated us, they wouldn't be wasting compute on simulating all the boring and uninteresting things we have in our world.
I just don't see why would an intelligent being (especially if they're a human descendant) choose to simulate our world the way it is right now.
Whoever is simulating us might be so far ahead of us that they simply don't see or care about what is bad and cruel and tragic. It's like if we would simulate an antstack or a beehive. We would think it interesting but wouldn't really care about the ethics of ant-brawls.
Assuming that our lived reality truly is just a simulation, I think it's important to also wonder why we would be being simulated. Not that we could ever hope to know or even comprehend our creator's intentions, but perhaps it's for research?
Could it be possible that they've just rented an RTX 40,090 and are simulating the entirety of our Universe to learn about how their (our?) species developed? Or how certain things would change if variables were altered? Perhaps there is a "multiverse" of infinite selves, but the multiverse is just a all the previous simulations that were tweaked slightly differently and had a different result.
Maybe changing the starting position of 1 atom in the beginning of the Universe has a butterfly effect that would entirely evade our assumptions. If we had the compute, why not simulate every possible reality? Perhaps there is 1 simulation that's occurred where everything was perfect, without anything cruel or unethical! And if we're gonna go as sci-fi as simulation theory, I don't think it's a far assumption that we could build things like fusion reactors or Dyson Spheres. We could learn so much, especially if the agents behaved naturally and had no idea that they themselves were simulated.
I don't actively believe we live in a simulation, but I think actively believing that we don't just doesn't make mathematical sense.
I'm reminded of the Culture novel Surface Detail, which basically revolves around d the ethics surrounding simulating consciousness. There is a society in the book which runs afterlife simulations, including a pretty horrible hell. Conflict over whether this should be allowed to continue is one of the main drivers of the plot.
My counter argument to that is try designing a more fair universe given all the known “natural laws” to exist. It’s pretty balanced from a “finely tuned perspective” to the extent everything exactly depends on the other.
(The argument then of course continues that if we would, our world's inhabitants would some day too, ad infinitum. Given such a stack, the chance that we're actually still in the top layer is very small.)