Go to 46:08.
"Imagine a movie that's trying to be a serious drama. A serious drama where the main character shoots 860 guys. And then goes to his family at the end and you try to have this touching moment where he's caring for his family. It simply doesn't work because you've changed the value of human life. Like, part of that shooting 860 guys was burning down a village of poor peasants so that you could get in with the Mexican army. Throwing molotov cocktails into their house. Those are families just like your family that they're trying to have their poignant moment with. That poignant moment just does not work in that kind of game."
I don't really agree but I think its that separation of story and gameplay that just comes naturally in my mind. I also think RDR's ending did work as intended in many, many peoples minds.