That's scary. Where to even begin to convince them?
If nothing more, there's a few words for people who are aware of this and actually do something about it, you can read all about them by looking up news articles containing words like "Terrorist", "Public enemy", "Anarchist". In some cases it is thinly veiled in unrelated words like "Nazi" even though if you really think about it, the problem with "Nazis", whatever that even means today, was fascism, same fascism that you're dealing with right now, but it's totally not fascism however because fascism requires Hitler, and trains, and uh, public shootings or something.
Setting up a system that invades privacy to catch crimes is bad because once you have that system, all you need is for your government to criminalize good things to reach a dystopia.
In order to avoid that, you'd have to actually run that dystopia, but dramatically and at a small scale.
A great example could be a US state where abortion is illegal and gives actual jail time (I think that's a thing, not sure). You have one of those states put into law that online services must scan for the word "abort" then actually find and put women that had illegal abortions to jail over this.
If you did that, you might get the congress to make digital privacy a protected right at the national level.