It's an intresting theory but I have my issues with it. For a start, what we can simulate would be defined by what we input into it, so it makes sense a computer model of the universe as we know it ends up creating a universe very much like ours. I don't think that corilates to our universe being a simulation just because we can model it in one.
... and i still say regardless it makes no f**king difference to my life lol. Unless we can start simulating some lottery wins for me