I can appreciate the comedy of a guy calling himself 'the real Paul' who asks why there are no big Hollywood movies featuring little grey aliens. ;)
Back in the 1940s it is said that the US military took over Disney studios, after they realized that Walt was able to manufacture the imagination of entire generations of children. That propaganda tool has been very effective, having taken over the whole film industry now. There are probably benevolent aliens out there who would be great allies for humanity, yet practically all we see are the evil ones. Since War of the Worlds hit the American radio waves so long ago, the reaction of the chemical that is the public mind was too dramatic to ignore. Fear not only sells, it can guide a herd mind to do the most ridiculous things.