There is an easy way for Apple to handle this. During iPhone setup present the following screen:
"We here at Apple do not want our servers to host images of exploited children, but we also respect your privacy. So you're free to use your phone with the photos stored locally, but if you'd like to enable iCloud we need you to press the button below to *install* our CSAM detector."
Then the argument basically goes away. It's like a virus scanner that you voluntarily installed. But having it baked into the phone as it ships rubs me the wrong way.
"We here at Apple do not want our servers to host images of exploited children, but we also respect your privacy. So you're free to use your phone with the photos stored locally, but if you'd like to enable iCloud we need you to press the button below to *install* our CSAM detector."
Then the argument basically goes away. It's like a virus scanner that you voluntarily installed. But having it baked into the phone as it ships rubs me the wrong way.