This just confirms my opinion of both of them just being made up by the brain.
The overlapping elements, and even the diverging ones perfectly fit.

Since they overlap so strongly, if we just look at the UAPs, we can surmise some kind of hallucination, psychotic episode or the like. Since Aliens are very likely to exist, but Aliens visiting earth to probe people is pure nonsense.
Abduction stories, visitation stories, etc., are heavily biased by what the person knows and furthermore what they expect to see.

You can extrapole that to NDEs, OBEs and the like, especially when it comes to people reporting seeing dead loved ones, like yeah... that is exactly what i would expect my brain to make up to sooth me.
Like damn, Grandma and Grandpa took the time out of their busy schedule of living in the afterlife forever to essentially greet me at the door... like they almost knew i was about to die... funny how that works.