We're slowly heading there on one level whether developers like it or not because of more realistic graphics. The more believable and emotional characters become, the more real their pain and suffering feels. A notable point for myself was Soldier of Fortune 2, and accidently blasting a maid with a shotgun once, and seeing her pathetically try to keep her guts from spewing out of her gored torso with pain wretched and animating/developing realistically on her face.
It's something that comes up in GTA violence discussions a lot. Care-free violence is fun when it feels comical, but what about when graphics get so realistic that it feels more realistic and emotional than a movie? Don't get me wrong, I love my game violence, and I don't want to see anything change. But none-the-less, I think there will be a point where games and the characters in them (and the emotions they invoke) will become so realistic that the thought of beating some 35 year old woman to death with a baseball bat will cross a sensitivity threshold with many people.
Anyone remember that video from E3 with a woman crying? I recall a post on IGN asking if people would be able to shoot her in the head in that scene, and a surprising amount of people (if I remember correctly) said they just wouldn't feel comfortable. She just felt too real to them.
I realize your topic was more directed at content and how it rarely concentrates on the horrors of war, and to that I have little to add. Fact of the matter is, developers by and large still want to make war fun, and true horror isn't fun. However, some of those horrors will become more realistic as a side-effect of our desire for more realistic visuals.