If something like this was in widespread use it would have much more impact since countries would see whole swathes of the internet immediately go dark when they make stupid laws.
My kids have learned a huge amount from the internet. I have guided them, discussed what are credible resources, the harms possible etc, who they talk to and what they tell them....
There are solutions that would make it easier for parents - people need tools to manage this. Require that children use child safe SIM cards in their phones (they are available already - EE advertisers them). Home internet connections should be by filtered by default that can then be turned off (or off for particular devices in the ISP supplied router that most people have).
Who do you want your kids to communicate with over the internet ?