The proper level is actually the device. The government doesn't care about how you arbitrarily divide the device software into components - only how they are non-arbitrarily provided by different people.
The proper thing is to strictly outlaw kids using the internet. There is nothing of value for kids on the internet, and even if there were, there are technical means of allowing users to use applications without generalized and ungated internet access, for instance roblox could be distributed through an age vetted app (including vetting adults too), the app could get internet access but disallow general internet browsing to arbitrary hosts.
