what I read was that apple is literally scanning for the hex code of the known images. I dont think its doing anything more than a straight image search, looking for exact duplicates. Not trying to tease it out with AI interpretation of furniture in the room.

for one, this 100% guarantees all the hits will be accurate (I think apple said 1 in a trillion false positives), but if you find someone with 1 known illicit image, A. you probably want to chat with them, B. they may have others, which can be obtained with a search warrant likely justified by finding the first image. Of course... then we'll get into the issue of how to search a locked phone, but maybe the person will be ignorant enough to unlock it, or use biometrics which I dont think are protected, or maybe the FBI has their ways around it anyway.