This is a stupid argument. First, the ESRB is not the dictator of who plays what games. They are a recommendation group. Parents may want to consider what they say, but it should not be left at that. For example, sexual content is much worse than violent content in their eyes, and I'm sure we all agree that's stupid.

Second, kids play CS and TF2. We all know this, and Valve knows this. That's not a bad thing, even if they're rated M. I don't think they do any harm, and CS at least probably does some good, with learning teamwork and stuff. Valve then uses their platform to push gambling, which is wrong (it's psychologically manipulative, when they could just sell skins outright without manipulation) regardless of age, but particularly bad if they aren't trying to prevent kids from participating, and they aren't.