I agree with your post almost in total. However the footage and radar paints of the F-18s some years ago off the coast of California defy any rational explanation. If this was a manned craft of our design doing the speeds and changes in direction of this UFO the G forces would have made them into pink slime. If the film is real this was an alien craft. If it is not real, why in the hell did the defense department release the film. Something strange is going on.
Relative to a civilization that can cross interstellar distances and observe us, we would be just curious bugs for them to look at and study. I hope they like bugs.
Like as in to eat? {{{shudder}}}
I still like to keep an open mind, even to the malevolent possibilities, but I have a problem with issues like “what could they possibly want?”. Earth has no resources that you can’t find more abundantly somewhere else. Water, gold, both can be found in far greater amounts in the outer solar system and the asteroids. If they want a livable planet, I’d think it would be easier to terraform a nearby planet rather than transport their entire civilization light years across space. It makes no sense to me, but maybe I’m just a stupid human with a puny brain.
They would either have some form of a robust environmental ethic, or not. Either way, it's difficult to imagine they would want anything from us. It's also difficult to imagine that they would see us as a threat.
High technology and exploration would seem to imply curiosity, so observation and non-interference is a realistic possibility, assuming that faster than light travel is possible (big assumption), and assuming that intelligent aliens exist at all (big assumption).
If I had to guess today, I'd guess that faster than light travel will never be anything more than a convention of science fiction and that we therefore will never really have a definitive answer about the existence of intelligent life somewhere other than earth.