For instance, if we see something like these, the explanation is going to be drones:
https://www.youtube.com/watch?v=ZVTlN41Mr9w
https://www.youtube.com/watch?v=U5CSReaPNcg
https://www.youtube.com/watch?v=1a95YERVRBM
If we see something like these, CGI, I suppose:
https://www.youtube.com/watch?v=8wskl8NJ2wU
https://www.youtube.com/watch?v=cE-Yrv1-chI
https://www.youtube.com/watch?v=2JRi7VUZTcA
This one is taken by a military grade camera at night, I suppose it could be a drone or a bird:
https://www.youtube.com/watch?v=c1qiZ_L8wX4
Because it's not reproducible it's always possible to explain away everything. It's an epistemology nightmare but I find it very interesting, specially when you have testimonies from people that you don't have a reason to doubt. I have to think if, maybe, our priors are too strong in one direction.