Apple gets hung up on weird stuff. Likely doing work phone side was an environmental argument. The amount of energy used to decrypt server side to create the ha

Apple gets hung up on weird stuff. Likely doing work phone side was an environmental argument. The amount of energy used to decrypt server side to create the hash was marginally larger than the amount used by the phone pre-encryption with cost of transmitting. (Bonus that the energy and CPU was paid for by the client). The result for either location is identical.