[jasamer]

The CSAM scanning solution allows law enforcement to do one thing, assuming they have full control over the image hash database: find people who have multiple photos that are already known to law enforcement that they upload to iCloud.

How would you use this to find criminals in general? I have a hard time to think of a very useful example. Maybe photos of bomb plans downloaded somewhere from the internet that are known to be used by criminal groups?

As to what stops a pedophile or a journalist form disabling iCloud photo storage: Absolutely nothing. This solution is supposed catch people storing CSAM photos in iCloud, that's it. A careful pedophile will not be caught by this.