Robin Hanson—the guy that came up with the grabby aliens hypothesis that seems to have solidified itself within the EA-rat zeitgeist—also has some very interesting and fun ideas on what UAPs might be—some that actually answer some of your questions:
https://www.overcomingbias.com/p/ufos-what-the-hellhtml
https://www.overcomingbias.com/p/ufos-what-the-further-hell
I’m surprised I don’t see his blog cited anywhere by you or mentioned anywhere in the comments.
Robin Hanson—the guy that came up with the grabby aliens hypothesis that seems to have solidified itself within the EA-rat zeitgeist—also has some very interesting and fun ideas on what UAPs might be—some that actually answer some of your questions:
https://www.overcomingbias.com/p/ufos-what-the-hellhtml
https://www.overcomingbias.com/p/ufos-what-the-further-hell
I’m surprised I don’t see his blog cited anywhere by you or mentioned anywhere in the comments.