The number of potential obstacles barring humans in the future from creating such technology are too great.

The argument

Nick Bostrom, within his own 2003 philosophic theory, claims that a number of factors must contribute to the success of the advanced human civilizations in creating a complex universal simulation. Proponents of this position argue that those factors are precisely where the theory breaks down. Many critics and opponents of the theory itself believe these barriers to be too great for the simulation theory to ever become reality, citing the exponentially increasing unlikelihood in the theory ever reflecting physical matter as the complexity of hypothetical scenarios rises. The difficulty compounds rather than merely accumulating, so each added layer of fidelity makes the whole proposition dramatically less probable than the last. The first barrier is capacity. Bostrom posits that the fraction of advanced human civilizations that would ever be able to reach this level of complexity in a simulation is incredibly close to 0. A conclusion that requires such simulations to be numerous cannot rest on a capability that almost no civilization is expected to attain. The second barrier is motive, and it is independent of the first. Even among civilizations that could build such a thing, the likelihood of "posthuman" civilizations looking to move backward in time to create a simulation for the many generations before them is very low. Being able to run simulations of one's ancestors is not by itself a reason to run them, and the argument needs both the ability and the intention to be present together. What proponents take to be decisive is where these estimates come from. Even Bostrom, the man who practically invented the scientific and philosophical framework for the simulation theory, doubts the probability of such a phenomenon ever occurring, and on this reading his tentative mathematical calculations disprove the theory itself because of the astronomical odds that it would ever truly exist. Since the obstacles are too great on the theory's own accounting, we are not living in a simulation.

Premises

Counter-arguments

Decreasing probability does not equate to the theory's complete lack of plausibility, which is why it is called a theory. Yes, there are many factors leading to the prospect of simulation that come across to mathematicians and physicists as unlikely now, but advancement in technology clears away all predictability for the future and there is no definitive answer for how far human can come with computing power. Many natural phenomena in the physical world seem unlikely when solely dictated by probability, yet still, they occur all around us. To completely discount the anomalies in the observable universe to refute the simulation theory is vastly illogical.

Rejecting the premises

[Rejecting P1] Lack of probability does not necessarily equate to lack of plausibility. In other words, an improbable premise does not always lead to an impossible theory. [Rejecting P2] Relying solely upon mathematics disregards all possibility for anomaly within the universe, and the simulation theory is not necessarily impossible if its premises are improbable. [Rejecting P3] From the evidence given, no one can definitively say we are not living in a simulation.