Disagree. I think this is a boon to E2E encryption. However you might feel, content filter legislation is unstoppable. It will just take a few high profile media cases for E2E encryption to be killed, otherwise. This is the right (privacy-conscious) way to implement it, on device. Google has been doing this for years, yet server-side. I recommend reading the actual docs: https://www.apple.com/child-safety/