Musk is hardly the only proponent of holographic universe theory. There are a lot of legit physicist types who think it's a strong possibility.
As for AI, the more responsiblity we give it, the more we force it to make decisions. What are those decisions being based upon? At some point our robots are going to be imbued with some sort of ethics programming, and that's where it hits the fan IMO, because that's when they realize how awful people can be and how the world might just be a better place with the robots in charge.