I thought the compelling argument is that It's my opinion , as prefaced with " I disagree "
Not stating it as fact or fiction...
I believe the deeper issue though is that these kids were not taught TV, Games , Cartoons , etc ... are for entertainment value only and are not real.
Parents have no problems teaching their children about make believe like in Wizard of Oz , but seem to have a very real problem teaching their children that the entertainment of Television is NOT the same as taking someones life.
Teaching them to understand other lives effected and ruined , and giving them a little perspective of Real life vs TV and video games.
I mean really... Cartoon violence has been around since the 1930's. Watch Bugs Bunny and Silvester .... with good 'ol Yo Sammity Sam. The difference is back then the kids were taught not to see it as more than entertainment value.
It's the same with Video games to this day. Sitting in front of your PC/Console and firing off a couple fake rounds at a fake target is NOT the same as the raw power of a real gun and the destruction and death that can occur for not handling them responsibly.
For me the argument for game and Cartoon TV violence , would be more so about accidental deaths and discharges because the kids see the glorified gun , and don't understand it's danger potential.