That is an Apple current policy, not any sort of law. If the FBI wants to know if there are any collisions on a particular phone, that will be shared. If the FBI wants to know of all single collisions, that too must be shared. A corporation's internal policy decisions are nothing when faced with a government official carrying a warrant. If they have data indicating possible crimes, no matter how small, they can be forced to divulge it to investigators.

Unlike Lavabit, I don't think Apple will ever close up shop to protect customer data.

Well of course if you believe that FBI can ask Apple to share anything and they will agree, and not tell us, then what is even the point of this discussion? Then they already have access to every photo, every email, every text. Because Apple controls those apps on your phone.

The difference is that now they confirmed that they do search your private images.

Why would that make it any likelier that they are also secretly searching your files, with another method? Seems completely orthogonal to me.

They showed that they are willing to do it in one case. Why not in other cases?

I thought the system is designed such that the threshold must be met to check the matches, i.e. it’s not possible to follow the FBIs request without changing the entire system.

int matchThreshold = 30;

if (numMatches > matchThreshold) { snitch(customer) && customer.life.ruin() }