That is a perfect description of angels. The reason I qualified it as the angelic subset "demons" is that the behaviors reported do not comport with God's revealed will and are typical of resistance to it, which is what demons do.
The problem with your theory is lack of evidence; indeed, astrobiology is often scorned as "the only scientific endeavor which is completely devoid of data".
By contrast, we have an enormous abundance of evidence for angels (and for theophanies). So, the probabilities argue strongly for an angelic, hence demonic, explanation.
Biblical angels are "messengers" of course but there are plenty of other types of holy spiritual beings besides angels that we know little about.
And demons is another confusing term. Are they the spirits of the Watchers OR are they spirits of the dead offspring of the fallen Watchers (i.e., spirits of the Nephilim).
The Bible isn't particularly clear here. Even the Ethiopian Book of Enoch doesn't tell us that the Nephilim spirits will return in such the manner as we are now seeing.
All very strange.