IMO, the law should establish some parental rights over their children, I don't think this is controversial. You can argue with what the limits of the rights are, how they interact with the rights of the child, and how that changes as the child ages, but the basic ideas is pretty sound.
And then given that, it is the role of an elected government to determine all these factors, subject to review of the courts. That all seems to be working here.
It would be absurd for the UK to create a special exception to allow underage youths to consent to user tracking at an age lower than the standard age for legal consent in any other context.
But would you at that, this is a discussion started by a news article where one of the scummy companies is discovering what those consequences are. So something must be working.
[1] - https://en.wikipedia.org/wiki/Age_of_consent_in_North_Americ...