I think they are real; some are definitely man-made experimental craft. But the rest? Idk, if you think these are physical nuts-and-bolts objects piloted by alien scientists trying to study us or something it just doesn't add up; their behavior is too weird, nonsensical, dreamlike, and seemingly intentionally misleading/disinformative. I'm more amenable to Jacque Vallee's hypothesis that something much weirder is going on; UFO encounters/alien abduction reports bear an insane amount of resemblance to archaic accounts of contact with gods, angels, and the fae, and contactees sometimes have visionary psychedelic experiences of divine revelation, cosmic information downloads into their minds, and other cognitive alterations. It all seems like different interpretations of the same phenomenon. Whatever is happening to these people is clearly a psychological phenomenon on some level at least, similar to states like near-death experiences or shamanic trances/psychosis happening to people with no history of mental health problems, but sometimes physical evidence is present too. So what is it? Fuck if I know yo, but I would be absolutely flabbergasted if UFOs are literal spaceships that broke the light barrier to come visit us.