These are the same clowns that have claimed to have extant physical samples of extraterrestrial materials, but only offered them to independent examination once, which didn't go well supporting their claims, and have paraded an endless number of excuses since while doubling down on claims it offers incontrovertible proof.
There's no big mystery here, these are relatively unsophisticated conspiracy nuts that got above average traction. That's it.
The trick is to remember that it is like the sql NULL. No unidentified object matches any other unidentified object. It is only once you identify the object can you claim that it is of extra terrestrial origin not before. And once you identify the object it is no longer a UFO.