http://ssd.iykpqm7jiradoeezzkhj7c4b33g4hbgfwelht2evxxeicbpjy44c7ead.onion/ps/module/how-encrypt-your-iphone
If you have an older device that can't be updated to iOS 16.3 or newer, enabling Advanced Data Protection is only possible if you remove your Apple ID from that device. In many cases, this makes that device useless. For example, if you have an older Apple TV that cannot be updated, removing it stops you from accessing the App Store with your Apple ID, preventing you from using Netflix, Hulu, and any number of other apps.