Ok, let's try to make this really super simple without all of the metaphysical or philosophical mumbo jumbo.
Let's, for the sake of the discussion, stipulate that the orbs are beings of some sort.
Where is the logic in a bunch of beings, who are benevolent, flying around in the sky so that they are seen, but choosing not to engage? Surely they would know that it would cause anxiety at the very least and panic at worst.
That does not seem to be a hallmark of benevolence.
Would it not be more logical just to remain hidden, if your goal is to observe and/or protect (protect from nuclear annihilation, to use your example)?
Can you address this by using logic and deductive reasoning, without saying things like "I've tried to tell you XYZ" or "You don't believe any of this anyway."?
I simply want to understand how it is beneficial to humans or these beings for them to come far enough into our world to cause anxiety and panic but not enough to bring any sort of clarity as to who they are or their purpose here, if in fact they are benevolent.
This should be really simple to articulate.