Again, I'm going by what I have seen and not opinion. We used to play "War" when I was a kid....simulating bayonetting our friends or shooting them point blank with a plastic Tommy Gun. But speaking for MY clan of friends, we had PARENTS who set us straight. Even the guys with divorced Parents.
About 20 years ago, me and my Brother were at an Arcade , "Dave & Buster's". We watched this kid playing a video game where you stand at a screen and shoot people. Looked like something used for Military or Police practice. It looked DAMN real. We watched this kid who was about 10- 11 years old play this thing as he stared with a glassy look. He never cracked a smile or looked like he was having fun. My Brother said to him..."Dang! You're pretty good at that!" All the kid could muster was a grunt / grumble. I'm not saying the games THEMSELVES are THE reason (Though I bet they HAVE to create at least some desensitized brains out there) It's the fact that kids are being raised by them instead of Parents. Social skills have gone to absolute crap. People do not know how to interact. Add that to people drooling into their phones 24/7 to look at Social Media which, MORE THAN EVER, is built to stir and anger, and we have a LOT.......I MEAN A LOT of angry people out there with ZERO clue how to handle their emotions. It starts at Parenting. These days, when little Johnny acts like an ass or gets in trouble, it's ALWAYS somebody else's fault.