I feel that it's the kind of scheme that requires too much cooperation from too many people and organizations with conflicting incentives. It's possible some countries would not want the hashes from certain other governments in the db at all. And then what? I may be wrong, but I also believe we can know how many hashes are in the db, which means that if it contains extra hashes from dozens of governments, it would become suspiciously large relative to how many CSAM images we know exist. Furthermore, in this scenario the db cannot be auditable, so the scheme falls apart as soon as some rogue judge decides to order an audit.

I honestly don't think Apple wants to deal with any of that crap and that they would rather silently can the system and do exactly what everybody else does than place themselves in the line of fire when their own unique trademark system is being abused.