[Haeuserschlucht]

I understand why you consider his question relevant. At the same time, it is worth making a clear distinction: OP does not formulate an alternative empirical explanation of physical reality, but rather a philosophical reflection on the consequences of the simulation assumption itself. In this context, the question of experimental testability is generally meaningful, but it misses the point here because it presupposes a scientific hypothesis that OP does not even propose. His objection would be justified if OP were to claim truth in the scientific sense — but he does not.