Earlier quoted context omitted.
Don't worry, as this is not about child sex abuse anyway. The legislators know, from experience, that it's hard to argue against measures to protect children from predators, and so they are free to launch controversial and unacceptable measures. Once in place, it will be extended to other purposes. The same as always.
The thing is, with current 'privacy-protecting scanner' designs, the scanner is running on every end users device, and it would be fairly simple for an expert to dump out the list of things being looked for. That in turn makes such a system far less useful to intelligence services and authoritarian regimes. You don't want to tell your target that you're looking for them and which keywords not to use! I wonder if this…
I think the Apple design used some fancy tricks to run the comparisons without ever decrypting the reference data and even if that wasn't possible almost every new device comes with some kind of "trusted" platform module that only "trusted" actors can access.