> The only acceptable solution would be for apps and websites to simply include a recommended age. Allowing parents to configure their children’s devices to block services that require users to be older than the specified age or that do not provide an age rating.

Agreed, just make age controls available to parents, optional, and keep the user age data on the local device. External hosts can verify against it in obvious ways. But isn't that what California's law said, that commenters on HN opposed so strongly?