As to the first, that there is any reality at all, is perhaps a question that the simulators, if they are evolved enough, and are seekers of truth ask themselves. And hence by making a simulation, and seeing it evolve in timescales otherwise inaccessible to a life-form, they seek the answers. I think a simualtion is a natural response, a logical way to seek answers for finite life-form facing time-scales beyond the ken of its living scale.
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The more important question is, does it really matter? From the perspective of a living being, the question about simulation is the question about mechanics of the world, about science, existence, chemistry, astrophysics, quantum. Science itself shows that this is all appearance. But it doesn’t change the basic fact of living. There is no decent exit except what provided in the natural course of birth and death. Meanwhile, my personal take is whatever it is, it is quite wonderful. Yes, it is not always great and there are pains and aches from life sometimes, there is unpleasantness, at times there’s voices, there’s the wonder at the sanctity itself. But still still still, being here is plenty. That we can begin where we are and try to make the best of whatever seems to be on the table in front of us is good enough. Perhaps that is a personal take. Perhaps yes, we are simulated. Either way, it is wonderful that there seems to be this something. It is a brief candle, this life, will pass before you know it. Meanwhile, have fun and do well and good. Take care of yourself and your surrounds, in expanding circles that you can sustain. Be well, do well. Enjoy the wonder of the being when you are quiet enough to do so. There's just this inner flame, the fountain, irrespective of the number of nested simulations there might be. There’s little else.