Please read the linked article before making baseless claims: > The communication safety feature [...] is available to child accounts signed in with their Appl

Please read the linked article before making baseless claims: > The communication safety feature [...] is available to child accounts signed in with their Apple ID and part of a Family Sharing group. This feature is off by default. In Family Sharing you can designate AppleIDs in your family as being child accounts. An AppleID is mandatory to use iMessage, so thats how Apple "knows".