Very well-written article and I agree to an extent. I wouldn't go so far as to say these games are designed to prepare kids for watching real life gladiatorial matches, but those games are definitely degenerate and designed to make us enjoy violence for violence's sake. They appeal to man's more savage instincts rather than his more sophisticated ones. I also think MMA ties in with this somewhat. MMA has absolutely exploded in popularity over the last couple of years and it's had me wondering why. I'm not some limp-wristed pacifist who thinks all combat-sports are wrong or whatever, but MMA is different to boxing and other combat sports in that it's a lot less "regulated" so to speak. What I mean by that is there's less restrictions on what you can and can't do, they're free to be much more violent and dirty than in other combat sports. This makes it less of a gentleman's sport like other combat sports(or well, they *used* to be gentleman's sports at least), and much more basal, animalistic and barbarian than them. And I think this might tie in with your points, it's accustoming audiences to enjoy violence for violence's sake.
I don't think that all violent games are bad though. Bad as in a waste of time and potentially sinful? Sure, same with most movies, TV shows and books. Bad as in especially evil and much worse than all those 3, or even designed to make us shoot up schools? Definitely not. Gaming as a hobby in general is a waste of time and most games either teach the wrong lessons, have occasions of sin as part of their campaigns/gameplay, or are just a very unproductive way to spend time. But they're no worse than violent movies or TV shows.