> It was in one of the articles earlier today that Apple has a distinct, secret algorithm they perform on suspected CSAM server side
But then they still need to upload the original image to the server, and what was the reason for doing the scanning client-side then when they still upload it?
>and what was the reason for doing the scanning client-side then when they still upload it?
Probably so that China cannot force Apple to hand over arbitrary images in iCloud (or all images in iCloud). With Apple's design the only images China can get from you are malicious images that people send you. If Apple scanned every image serverside without any clientside scanning, then theoretically China could get all newly-uploaded iCloud images.
But then they still need to upload the original image to the server, and what was the reason for doing the scanning client-side then when they still upload it?