To answer the first question: well, if the entire universe is a simulation, and "someone" is running it... that is essentially God. Just another name for it. They have complete all powerful control of our existence and of everything we can see or hear. So the question, to me, is just another way of asking if God or some higher power exists. Which people have been asking forever.

As for the question of life... I think that the people thinking of this kind of thing make optimistic assumptions as to how long intelligent life / technological civilization can last. We've been putting out radio waves for a little over 100 years. I doubt we make 1000. Whether we destroy our planet or an asteroid does or we descend into a non-civilized state.

So if you assume that highly intelligent civilizations last less than 1000 years... it's not that shocking we haven't found any. Not because they aren't there. But when the universe is BILLIONS of years old, if a civilization only lasts 1000 years, another one in the next star could pop up 1000 years later or 10,000 years later or 7 million years later, and even though they were right near each other they would never detect each other. Especially if interstellar travel is damn near impossible.

People who think civilization will always advance and we will last millions of years and will either invent warp drives or discover wormholes or last long enough to build a giant ark to send humans through the vast distances of space -- may be assuming too much. Life has probably popped up billions of times on the billions of stars in our galaxy, and some percentage of that life has become advanced, but if those civilizations didn't do something to make them able to last millions of years, then they would just be little lights popping on for a brief time and going off, and the chances of two of them popping on at the same time and being able to notice the other are pretty slim.

And the fact that we are protected on earth by a very friendly magnetic field that allows us to avoid being radiated... might be more of a fluke than people think. Maybe only 1 out of every 10000 earthlike planets has such a magnetic field. That drops the odds considerably. Solar radiation makes the trip to Mars very unpractical, by the way.