Having at least some experience with international police orgs, I can say that significant resources are dedicated to online crime (including CSAM) and their 'lived reality' is very much expending significant resources because e2e prevents low-cost surveillance.
So the attack line that 'none of this is sincere' is actively unhelpful -- since so much of it is sincere, it comes across at best naïve.
A better line, imv, is this: assume present goverments are entirely sincere. It doesnt matter. We cannot know the intentions of future governments. And we have good reasons to suppose that governments, in general, require extraordinary systems of checks-and-balances to be prevented from abuse of power.
So I'd advise not attacking people who are, very often, actually thinking of the children -- you're just antagonising the people in power. Rather, invite them to help you defend the liberal order of individual human rights that prevent state abuse of power. As a matter of fact, they really arent actually trying to create a secret police.
Enabling state abuse of power has a far far higher negative outcome than marginal increases to the difficulty of policing some crimes. In many cases, police agencies can find ways into criminal networks and can access messages using traditional policing.
A better rhetorical strategy here is supporting policing, providing significant additional tech expert resources to police, significant funding for 'online detectives' -- whilst at the same time explaining the high risk against mass state incursion into all aspects of our lives.