The simulation hypothesis is a view of the nature of reality, suggesting that our world is likely a computer simulation created by an advanced civilization. In contrast, illusionism is a theory about the nature of phenomenal consciousness, arguing that phenomenal consciousness is an illusion and can be fully explained in physical terms. I argue that if our world is a simulated construct, illusionism could be incorrect. Specifically, even if our phenomenal experiences can be explained as illusionism suggests, advanced civilizations could still create subjectively indistinguishable experiences by constructing a psychological system external to our world. Since we cannot determine which scenario we belong to, the illusionist explanation is not universally valid. Furthermore, I argue that even if the simulation hypothesis is impossible, illusionism remains flawed. Consequently, while the simulation hypothesis may function as a mere assumption, it exposes the inherent limitations of both illusionism and physicalism.