That's also assuming a data breach is required for it to be bad. What's to stop them from using this to tie a person to activity? Then it makes it really hard to view things your country/employer/etc might not want you to see, for fear that there will be consequences for it.

If it was just a magical switch, to ban people under a certain age from social media, I'd be for that probably. It isn't though. At best, there are consequences that effect everyone. At worst, this is a backdoor to push through internet tracking legislation.