Medications probably play a part, but video games don’t.
I’ve played plenty, I know people who have as well. I’m not about to grab a boomstick and go to town somewhere.
Same for movies, either we’re raised with values and morals, or we aren’t.
I think you are over-simplifying a pretty complicated situation.
Video games may not have an effect on you or me, but it doesn't follow that they can't have such an effect.
My wife and I sometimes watch several "true crime" shows on TV. She will often have bad dreams as a result. I have unpleasant dreams about once every several years.
People are not all the same.
Don't misunderstand me. Just because there might be an effect does not justify having the government step in and "regulate" the situation. It's up to people to find their own way in life, avoiding things which are unhealthy for them and seeking their own success.