I spent a great deal of my time between the ages of around 5 to around 8 or 9 shooting people with joined-together clothes pegs.
I spent as much time as any other kid watching Larry, Curly and Mo poking their fingers in each others eyes and hitting each other with frying pans. I saw many episodes of the Durango Kid filling bad guys with lead. I watched red stains spreading over the shirts of many other bad guys in murder movies.
And so did all my friends.
None of us, to my knowledge, has turned into an axe-murderer or violent person of any description. I think there are other factors at work here.

The so-called 'cause and effect' phenomenon is one of the most abused and carelessly/conveniently applied in all human relations.

If toys turned boys into violent offenders, then why is it that violent crimes have not increased significantly (per capita) because they haven't. 19th Century Europe was many, many times more violent than today. They certainly did not have video games.
Violence is a product of the whole social structure. To hang it on one (blindingly scapegoated) factor, to my mind at least, is an irresponsible and anti-intellectual cop-out.

There is more horror, fear and disgust in one bar-room fight than in a truckload of video nasties. Those who have witnessed or participated in such an event will bear this out, I'm sure.

I think we underestimate our young people. I really do. They know what is real and what is not.
I suspect some of our social engineers do not have the same capacity.

Cheers
Peter E