The united states is the only place ufo sightings happen. We arent the only place where military equipment is. It happens here because alien movies are a mainstay cultural aspect.
The things that cultures see during sleep paralysis vary depending on mythical beings or whatnot from that culture.
Unfortunately for the united states we had the movie ET and now everybody thinks they are being abducted by aliens every time they have sleep paralysis, or attribute something unexplainable to otherworldly alien technology
i get that. appearing to move in ways is not proof it actually did, etc. i just find my explanation the most plausible, because no explanation is plausible (that I can see)
That is a very level-0 thought response.
If there is anything on this level being hidden from the public then every world government is in on it, and the US government happens to be the one with the most leaks.
In addition; your own argument can be used against you in the sense that the reason the US populous is keen on spotting UFOs is BECAUSE of the prevalence of alien movies and TV.
Aliens almost certainly exist, they might be here or have been here they might not be (I don't feel strongly one way or the other but I will say there's plenty of wasteland or ocean to hide in if you didn't want to be seen). If they are/were here the options I see are
They are watching us monitoring our progress or waiting for a moment to introduce themselves when our tech or society evolves to a certain point
They are xenophiles who like studying 'primitive' cultures
They want/need something from earth and may be preparing an invasion. This one seems the least likely as if you had interstellar travel you could probably harvest resources from gas giants and asteroids unless the resource they want is us (earth organic life not just humans) like something in our genetic code, for example searching genetic code for a mutation to protect from a disease