alt Hacker NewsThat is the wording of the California law, IIRC. The age brackets are under 13, 13-16, 16-18, and over 18. It also requires the OS to provide only the minimum information necessary to comply with the law, and only when necessary to comply with the law.
What can I show to 16-18 year olds that I can't show to 13-16 year olds?
The real meat of the law is requiring websites and applications to comply with this signal. Which would be one good reason why there are so many categories of seeming little difference. This then gives them the opportunity to fine and harass developers out of business for the most minor of infractions or instances of mislabeling.