[throwawaygh]

This sounds like an excellent idea, but I'm worried about architecture/execution/implementation. Generally successful regulations set goals but don't prescribe how those goals should be met. There doesn't seem to be a super clean separation between "what" and "how" here.

[GoblinSlayer]

Implementations exist: Microsoft provides parental control filters, OpenDNS has community-driven content classification.

[throwawaygh]

Right. Building it is definitely not an Unsolved Problem, just like building a healthcare exchange website is not an Unsolved Problem. The problem is organizational and political, not technical.