In what way is it too simplistic? Is it not correct? I don't think I commented on whether or not it's good. Though I happen to think we'd be better off with a more democratically organized society.
Who is too blame for advertising to children directly? Is it a few people? Probably not, in fact it brings in a lot of talented people, of whom each may in fact have a negative opinion of advertising to children when asked.
If you are talking about giant corps that can influence rule(s), then ok, but these are not individuals but are the stakeholders and can be large swaths of people.