The problem is that the point is to root everyone's devices. Anyone explaining how easy this is would be pushed out of the conversation as fast as if they were advocating for single-payer healthcare.
edit: I've been advocating the nearly identical but opposite solution - restricted access sites shouldn't respond to requests that lack an appropriate age/content restriction header. If they do, jail them.
They're literally going to have to do this anyway. Rooting people's devices to force them to lie about their age when they install their operating system is an absolutely fake pretendy solution; the only way it works is if you have to verify your age with some government agency when you install an operating system, in order to make that OS age official. The point is the identification.