Yeah, and those are all movies that fit the description of what I said, there isn't any real sci-fi in them, just action-suspense-horror-popcorn-mainstreamism.
ok first of all, mainstreamism is not a genre.
An argument can be made that Star Wars is Science Fantasy, if one were inclined to do so.
Both Alien and Predator however are Science Fiction films. That they can be classified as SciFi thrillers does not make them any less SciFi.
But why don't you give us your definition of true SciFi, then we can put an end to this bickering.