There's are tons of credible people like esteemed pilots who say they've seen ufos do crazy things in the sky that defy known physics. There's sometimes whole towns who see spacecraft that look like alien ships. The point isn't to make the case that this evidence exists. It's to ask what the implications are and what it can be said to be evidence of.
I posted in another thread how evidence scientifically can exist for something even if that thing does not exist if we don't know that it doesnt exist. We know credible reports give indications that known physics are being violated and these ufos are often associated with aliens. Is it too much of a stretch to say that because the association exists that its evidence for aliens? Given known laws of physics are being violated doesn't that otherworldly technology give reasonable room to say it might be extraterrestrial? I think a skeptic could say the best explanation is that humans must have secret technology that defy known possibilities... and the fact that this explanation exists means it's jumping to conclusions to say its evidence for aliens. But how reasonable is it to think it could be evidence of the alien theory? Aliens existing wouldn't be a supernatural claim like many religious arguments when it comes to evidence. So isn't it fair to say it is or could be evidence for aliens?