Re: Deep learning?
You could argue that the existence of a Planck length is weak evidence that we're in a simulation - why would nature need to quantise everything, including distance and time, unless it was doing the equivalent of computing at a certain precision? Why isn't everything analog?
The second point is that the people within the simulation can't see the outside universe, so what we think of as very small or very large might be a small fraction of the scales available to the outside. If their Planck length is ridiculously smaller, like 20 orders of magnitude, then running us as a simulation becomes much much easier.
The third point is that the simulation doesn't have to run at or above real time - we're looking at simulating brains (I think from memory mouse brains?) but it'll run at 1% real time because we simply don't have enough compute available at the moment.
The fourth is that you don't know the bounds of the simulation - it's almost certainly the size of the inner solar system now we've got permanent satellites lurking around other planets and the sun, but it would be pretty trivial to intercept e.g. Voyager and produce plausible radio waves from the edge. There would essentially be a screen around the simulation beyond which everything was roughly approximated - think the draw distance in computer games.
I don't personally believe we're in a simulation, if only because surely no ethics board would allow the creation of an entire civilisation of sentient beings capable of misery.