> iCloud [...] will have to push the same hashes to everyone
Why?
What's to prevent them from pushing specific hashes to a specific phone?
Why?
What's to prevent them from pushing specific hashes to a specific phone?
There is no technical reason why they could not push individual hashes to individual phones, only policy ones.
I’m going to go further and say that people are doing a very bad job articulating why the incremental privacy risk of the scheme is significant, over the always-existent privacy risk of a proprietary vendor updating software they entirely control to scan data uploaded to a cloud service which guarantees no protection from vendor access. A later software update to include more hashes or whatever could always regress privacy.
The problem with this sentence is that Apple assumes that they can't target specific individuals because every iPhone and iPad user has the exact same database in their iOS device.
But what if they have a hash in the database where they know that only one person has this exact image on their device? This way you could single out one individual with the same database.