Video game restriction, as in the pushing of it into political discussion and policy, is something of a non-issue. It's something EASY for politicians to grab a hold of, focus on, and crusade for. That's to keep them from having to deal with DIFFICULT things like education, immigration, balancing the budget etc.
And all this arguing about responsible parenting is beside the point, because the idea of children not being able to buy mature games is beside the point. Seriously, it's not even close. All you people who are like, "I don't understand the fuss, so what if kids can't buy GTA4." are way off the mark. It's also not whether or not this would be logistically practical to enforce thanks to digital distribution or that all that would happen is talented designers move somewhere else.
What's fundamentally at stake here is whether or not games have first amendment protection. Under this law, it is criminally punishable to sell mature games to kids. The key phrase there is not "sell mature games to kids," it's "criminally punishable". Retailers would be taken to court, probably slapped with a hefty fine, just like if some construction company used aluminum cans instead of rebar. But we're not talking about a place where people work or live, we're talking about an entertainment medium.