The “alien” craze from the late 1940s and 1950s was based on real experiences from real people.
You may not believe that—but that is the way it was.
Here is one example:
https://en.wikipedia.org/wiki/1952_Washington,_D.C.,_UFO_incident
I used to be into that UFO stuff when I was a kid. Read Adamski and Frank Edwards books, believed there really were aliens visiting us. Not anymore. It’s been over 75 years since the Kenneth Arnold sightings and there has never been tangible proof.