It wouldn’t even work on paper. All it would take to twist this into something dystopian is requiring attestation for the age range, and knowing lawmakers, they would justify it as a countermeasure for kids lying about their age. Expand the feature as a web API so websites can use the “easier” and “more secure” system-level age verification process and—oh look, now we can’t use important websites without a commercial operating system.

It would be like Secure Boot but worse. At least with that you can turn it off or enroll your own keys.