Of course. Movies are an outlet to let off steam. We experience the violence in the theatre that is increasingly precisely because the pacified masses need a strong outlet to escape the lack of recourse for injustice in the real world.
This is a good explanation without supporting the idea that there is no propaganda of violence. There is. And btw, the US are one of the most violent advanced countries.
You're moving the goal posts. First you said that "pacifism is heavily promoted in mainstream media". When I pointed out that American mainstream media is absolutely riddled with "non-state invidualist hero uses personal violence to solve their problems", now you claim that the media is for "letting off steam".