Why do some people think all of reality is just a simulation ?

What I don’t understand is the viewpoint of various people that pop up here and in related subs, that UAPs and NHIs are merely observers into a simulation of reality that we mere humans exist within. Why, if all of our reality is just a big ass simulation running some idea of a physics, do these supreme overlords need to have us view them? Surely with a simulation they can pause, zoom and observe anything anytime anywhere without impacting said simulation? I.e. we should never see them. Yet people are seeing something.