> The scanner technology can also be used for detecting dissident journalism, but they say it won't be, it is just for preventing terrorism
This has always been possible with server side scanning. Yeah we have to trust Apple to not enable it for users who don’t use iCloud photos but we’ve always had to trust Apple given their closed source system.
Do any of the other companies control the database of hashes they use? A government could have already done what you’re suggesting but I can’t find a source where this has been the case.
iMessage photos do not automatically add photos to your photo library. Yes they’re synced between devices but afaik Apple isn’t deploying this hashing technology on iMessages between devices. Only for iCloud photos in the photo library.