CSAM can never be a policy issue with two sides, because everyone is in agreement that we need to protect children. The higher powers want to prevent child abuse, and CSAM is directly tied to child abuse. When people argue that "think of the children" can be weaponized to attack their freedoms, they wouldn't dare try to argue against the premise that children are harmed because of CSAM - not because the arguments will fall on the deaf ears of some governmental agents trying to push an agenda, but because the premise itself is sound.
As a result, people will focus their arguments instead on the technological flaws in the current implementation of on-device scanning or slippery slope arguments that are unlikely to become reality, the feature will be added anyway with no political opposition, and in the end Apple and/or the government will get what they want, for what they consider the greater good.
I think that absolute privacy in society as a whole isn't attainable with those values in place, and it raises many questions regarding to what extent the Internet should remain free from moderation. Are there really no kinds of information that are so fundamentally damaging that they should not be allowed to exist on someone's hard drive? If not, who will be in control of moderating that information? Maybe we will have to accept that some tradeoffs between privacy and stability need to be made for the collective good, in limited circumstances.