> holding parents accountable for what their children consume

There is a local dive bar down the street. I haven't expressly told my kids that entering and ordering an alcoholic drink is forbidden. In fact, that place has a hamburger stand out front on weekends and I wouldn't discourage my kids from trying it out if they were out exploring. I still expect that the bartender would check their ID before pulling a pint for them.

It takes a village to raise a child. There are no panopticons for sale the next isle over from car seats. We are doing our best with very limited tooling from the client to across the network (of which the tremendously incompetent schools make a mockery with an endless parade of new services and cross dependencies). It will take a whole of society effort to lower risks.

also there's a huge argument to be made that surveilling your kids is really really bad for their development

That same argument doesn't hold water on the internet. Its a communication medium. Its like a flow of information. You don't enter or leave physically spaces. the information flows to you where ever you are. trying to apply the same kinds of laws to the internet is a recipe for disaster because you are effecting everyone at the same time.