I've said before here that aliens as a hypotheses have little to no explanatory power. What I mean is that if you accept that people have witnessed this marvellous tech then either

(a) it's possible and someone has figured out how to do it, OR

(b) it's possible and someone has figured out how to do it and aliens exist

Don't get me wrong, I get it: the argument is that if someone on earth had figured it out then we'd simply have to know about it, thus it must have come from somewhere else.

It's just that I think that no matter how hard it is to believe that someone on earth could have invented this and kept it a secret, its still more plausible than aliens.

For anyone who has trouble with this, let me ask you to consider this: what if it's not that advanced? What if it just appears that way?

I claim that if someone has figured out a way to draw shapes in the sky that have no mass and move them around at will, then that is enough to explain most of it. Can I explain how they would do that? No. But is is less likely to you than aliens?