the difference between video games and other art forms such as music, movies, and comics is that you participate in video games and the game rewards you for that participation whether it be jumping on goombah's head, getting high note streaks in guitar hero.. or slaughtering people violently whether it be with a blade or gun.
Actually, you aren't factoring everything in to your thought process about games vs other media. Let's see if I can articulate this properly.....
Games don't look real, or even showcase reality in almost any way. Doesn't matter how good your system is, games still have a "fake" feeling on them. Sure, you are part of the game, controlling the actions. But you never truely say, " Damn, I feel like I'm really in this world." There is always a seperation with games that makes you , or at least 99.9% of people, say ," This is cool, it looks awesome, but I still know it's a game." Sure, they have some things that relate to real world, but there is always some boundry, missing element, or something that gives away that it is fake.
I won't touch music, as that has a way of touching people's "soul" in a way that no other medium can. Music can drive people to suicide, to remember things that make them happy or sad, and many other ways.
Movies I'd say have a bigger impact on how people can relate to the world though. Why? Because they combine not only realistic looking scenerios, but music that can grip you and move you. I remember sitting in my apt with a few friends, where for 2 days, we watched Sopranos for abuot 30 hours out of 48 hours. After all of that, we all had this sort of "ego" and feel to the world, that was brought upon us from the show. It was able to grip us in enough, to where after watching it, we had this alternate reality of what life was for a bit. Sure, we knew it wasn't real, but because of how well it was shot, it had a huge impact on our perception.
I've never had a game bring me in, cause emotions on such a level, as to what Movies do.... Except maybe Journey... That game still moves me
But other than that, I don't think games have any impact on 99.9% of people who play them, in such a way that it affects their view, actions, or reality.
TL:DR : I've never had a game so bad that I had to turn away or stop playing. I've seen plenty of movies though that are so disturbing, I had to either turn away or never watch it agian.
**** I hope I said that well enough.... pain killers kicking in
In the end, the real truth is all of this is about how mentally stable a person is. No rules/regulations will really ever solve that. Some types of mental illnesses only show up at certain times. It is really hard to diagnose someone with a mental illness until they actually have it, and even then, with healthcare so expensive, most don't get treated.