For many years now, most people have gone around believing that UFOs/UAPs, if real, must be visitors from outer space. But as has been said time and again, that hypothesis simply does not explain many of the things that people have been reporting for a very long time.
According to Jacques Vallee and Eric Davis, in their 2003 paper, our hypotheses need to get a little stranger and our view on the nature of reality needs to be revised.