Whatever our world is, it is real because we have given it this definition. Sounds silly, but it is totally irrelevant if it is unreal from some other vantage point we don't share. It is possible there are higher realities. It is also likely we will never truly understand our own. We are not designed to. We are designed to live, to flourish, it does not matter if we can be perceived by entities in another reality or not, nor even if they are responsible for our existence. We are not designed to "know" anything. What we call "Knowing" is just an emotion. I am not saying it is irrelevant what actions we take, there are consequences to actions. What I am saying is that all we have is feedback in the form of sensory data, it serves us. We detect useful patterns. That is it...it should not be confused with some mythical "knowledge" stuff. As "knowledge" is not "real", there is nothing to let us down about the state of our "reality".