This is not the case. People are guessing about how it works and getting it wrong. The device doesn’t know if there’s a match or not. The logic is not “if there’s a match, tell Apple”, the logic is “attach a safety voucher to every iCloud upload and let Apple figure it out on the server”. You can’t flip a switch and just run it against all photos on the device – the iCloud upload is a part of the design. If Apple wanted to scan all the photos on your device, they would have picked a different design for this. If Apple change their minds and want to do this in the future, they need to redesign how this works, it’s not just a policy decision.
