I suspect that a closer analogy is the classification system on films - which as far as I know is in effect in the vast majority of the world. Governments long ago decided that certain things are far too extreme for (young children / older children / anyone) to see, and have been censoring or restricting access to video media ever since.

Now that the internet is becoming mainstream, and a powerful provider of videos / pictures, they will seek to install similar systems to censor or restrict access.