Presumably the cloud synchronization checks are not a feature Apple wanted to add, but one which they had to under US regulations. Other providers have done this for years server-side, but Apple needed a different approach since the photos are E2E encrypted[1]
It is not a ML model but a list of known image hashes, and is only enabled for US-based accounts, furthering my suspicions this was minimum-effort for regulatory compliance.
Note they _do_ have a feature (also announced today) that uses ML models, but it is meant for local filtering and parental controls/notifications. This feature is also US-only and the parental notifications policy is fixed and age-based. I believe this is both to fit into regulations (e.g. US recognition of rights based on age) and into cultural norms.
I suspect they will have different rules in different jurisdictions when this rolls out further in the future.
[1]: With separate key escrow HSMs for account recovery and legal compliance with e.g. court-ordered access.
It is not a ML model but a list of known image hashes, and is only enabled for US-based accounts, furthering my suspicions this was minimum-effort for regulatory compliance.
Note they _do_ have a feature (also announced today) that uses ML models, but it is meant for local filtering and parental controls/notifications. This feature is also US-only and the parental notifications policy is fixed and age-based. I believe this is both to fit into regulations (e.g. US recognition of rights based on age) and into cultural norms.
I suspect they will have different rules in different jurisdictions when this rolls out further in the future.
[1]: With separate key escrow HSMs for account recovery and legal compliance with e.g. court-ordered access.