because it can be observed easily by any person. You can run your own experiments of observation on yourself and determine that playing a first person shooter alters your thinking before and after game play.
It is about like a debate of determining if there is really a rock in front of you or that it is simply a 3d image and you are also a 3d image created by a hidden software program that is the universe we know.
In my opinion a rock is a rock.
But the industry cannot be regulated simply because the media lobby is far more powerful than the NRA. They can make claims of a violation of freedom of expression.
My argument against the violent media is that it incites violence. I grew up during the era when bugs bunny and the lone ranger turned into the chainsaw massacre and the Dawn of the Dead.
I gave a link in an earlier thread showing the research linking violent video games to violent behavior which of course in a debate will be discounted by the opposing side. However I provided a source but those who criticized the source never provided one of their own.
This is the report by the than surgeon general Jesse Seinfield
A short biography