Of all the current US conspiracy theories, the UFO/UAP conspiracy is still the most interesting and fully developed/ongoing conspiracy space. Just check out the recent 'Age of Disclosure' documentary from this year.
I'm not arguing a position on the theory, just saying it's very active and has the old-school qualities that were present in the 90's.
Pilots from the Eastern Bloc and NATO countries have had sightings. It's not just a US thing. People have been claiming to see them for longer than the USA has existed.
IMHO, the whole social/psychological aspect of the "conspiracy" or phenomenom or whatever you want to call it is at least as interesting as the phenomenon itself.
There's some genuinely weird shit unexplained, I'll give you that. Unlike Bigfoot, where you can look at a map of the historical range of bears and see it exactly matches where all the Bigfoot sightings are.