It seems to me that it should be impossible to truly prove that the universe isnt a simulation. If you lived in a simulation, then the simulator theoretically can control everything that you experience, to include things like the activity of your own neurons and whatever else plays a role in your thinking. As such, they can, if they wish, make you believe that you have seen something that is inconsistent with a simulation, even if you have not, make you believe that something you did see is inconsistent with one even if it isnt, or cause you to believe that a certain chain of logic must rule out a simulation even though it doesnt. As such, there is a subset of hypothetical simulated worlds in which you are absolutely but falsely convinced that simulation is disproven. How can you tell the difference between one of these and a "real" world where you really have disproved simulation?