I get that the rate of improvement in game simulation will eventually lead to experiences that are indistinguishable from reality, however, how did he calculate the one in a billion chance that we're not in a simulation? That just seems like a wild guess to me.
Think of it this way, how many times has our civilisation run the Grand Theft Auto simulation? What about all the future GTA session that we haven't run yet. It's got to be many many millions.
Now GTA isn't a very sophisticated simulation, and the characters don't have much AI, but either no civilisation ever develops the tech to make a "realistic GTA", or no civilisation ever wants to run a realistic simulation, or there are many millions of realistic simulations in existence.
And if there are many millions of realistic simulations, and only one real universe, it's literally a one in a billion chance that were in the real universe.
In this context, why do we think there would be many other civilisations? In the context of the Fermi paradox we think there would be because the universe is so huge and we can calculate that there would be lots of planets capable of supporting life. That said, the structure of our universe is irrelevant if we're considering whether it is a simulation. The "billions" number that applies in the case of the Fermi paradox doesn't apply to this conversation. I'm also wondering where it comes from.
