My feeling is that surveillance states are more or less the norm, and it tends to become controversial as a sort of stand-in for other issues. So, for instance, the DDR's extreme surveillance apparatus becomes a sort of explanation for why this relatively bland state was actually a historic example of evil.
In england, there's a (very mild) controversy about the use of secret police to surveil activists - it became controversial because several of them had sexual relationships, and even children, while in their undercover role. One of the curious features of all this was who merited attention. One group of vegan restaurant connoisseurs, who met on fridays to review welsh vegan diners, discovered that one of their members was a police officer, for example.
This surveillance, which really had no bounds, including the surveillance of sitting government ministers (always labour, fwiw), is actually very typical, historically speaking.
So, while I'm broadly in agreement with you when it comes to the dangers of surveillance, I think we've all had and lost this argument in the past, and the fact is, if the state historically wanted to destroy or persecute a specific group, paper records were always enough. That means that if you want to make meaningful progress in the face of this information asymmetry, you have to find wedge issues.