I see room for two kinds of simulations, both of which Dawkins must acknowledge as possible.
The key phrase he makes, near the end of his answer, is that if a teenage boy could design a simulation, that he would have to have it operated normally according to rules that mimic physical laws.
Now, let's think about that.
Suppose our teen creates such a game, whereby unwitting players enter the Game without knowing it is a virtual reality. As part of his agenda, he sets things up so that mountains are "virtually" impossible to move. In time, the players learn that they can move mountains within the rules, by building trucks and cranes that meet the Game's requirements. Much labour and planning involved. And where manual labour is required the Game can be tweaked so that the player feels ever-increasing degrees of effort as he tries to take on more work, until he reaches a limit of course, as we all do within reality.
And so, after many decades where much learning is involved: learning that includes The Game being the only reality. That we all cease to exist after we leave the Game. That it takes this much science and that much physics to be able to take on the task of moving a mountain---
As one stares at the mountain from within the Game, knowing all of these things as he does, the mountain rises up in the air and appears to fly across the sky until settles some distance off to the left.
Our player is at a complete loss to explain what happened. What has happened, is a simple select-and-drag computer move, where the 'mountain' is simply re-positioned, according to higher laws that have to do with computer technology, rather than any of the rules that apply to within the Game.
Other players - some, not all - will surely say that such a think never happened because mountains don't fly. And here's the analogy. The world's spiritual tradition speak constantly of miracles. Seen more prosaically, perhaps these miracles are simply manifestations of a higher physics. Of course, it is easy to dismiss all of those testimonials as fiction, since they are relegated to an obscure past. But such denial is not so easy to apply to similar present-day events.
One such event was Fatima, which Susan recently said she supports being buried. But she failed to provide a shed of evidence that shows why this event is likely to be normal. This is typical of the denialists. At the end of the day, when evidence doesn't support them, they must deny, deny and deny. Better to ignore the evidence, as Susan recently advocated. At least that way one doesn't have to confront the embarrassment that so often accompanies carte blanche denial.
There's a lot to like about simulation theory, but it may be that the 'real' universe itself is based entirely on information, just like computers are. Staying with my one example just a little longer: rather than question whether or not tens of thousands of people actually saw the sun dance, or a ufo, etc, on an appointed day, the better question may be to question the nature of reality itself.
In recent years we've become too hooked on the myth of the physical universe being all that there is. We act this way while conceding at the same time - unless we don't mind sounding ignorant - that the physical world is 99.9999999999999 percent empty space, that thought shapes matter at the quantum level, and various other things that speak to why what greets our senses is NOT to be taken for what it appears to be.
Think about that. Simulation theory, by it's very nature, presupposes two sets of laws of physics (as a minimum): what causes the Game to function normally, and what causes the normal process to be interrupted.