[koolhaas]

Of course, but it's a kind of last resort thing to support a valid legal process they cannot (and probably don't want to) skirt around. They also publish data on warrant requests.

To me it's pretty clear they are doing the absolute minimum possible to keep congress from regulating them into a corner, where they lose decision making control around their own privacy standards. The system they came up with is their answer for doing it in the most privacy conscious way (e.g. not decrypting user data in icloud) while balancing a lot of other threat model details, like what if CSAM-hash-providing organizations provide img hashes for a burning American flag, and lots of other scenarios outlined in the white paper.