I don't think we need computers per say for the argument that "this reality might not be genuine" is a worthwhile argument. I don't think this is a computer simulation but there might be a possibility that this world is not real (by real I mean outside the senses and outside one perspective). Perhaps there is a world in which we are all a unified consciousness in which there is no negation (I am using a Sartrean philosophy). I have studied various philosophers who have sought out this answer (the most famous being Descartes). To those who claim that "the idea that this world is a dream is ridiculous and that we could never have a consistent dream like this", I reply "how can you assume you are autonomously dreaming?". Perhaps we are being given the dream and what we perceive is how we are able to process this dream. We cannot help but to follow the breadcrumbs given to us. One problem that humans have that makes this such a hard question is that we can't get into another person's perspective. If we were able to perceive outside of ourselves and through someone else that might solve a few problems. More info on why we have such a hard time absolutely validating the authenticity of our reality?