People suspected there was funny business going on since the Patriot Act was passed in 2001. By 2003 gangs were aware government spied on phones at scale. NSA regularly came up in my high school tech class in 2004, in connection with War on Terror. By 2005, the program was confirmed.
Lots of people know lots of things. The problem is those things aren't always true. And until there is a defacto public acknowledgement of something many people defer to the 'official position.'
Here's a present time one for you - all US based cloud providers, including Apple, are providing full (and probably indirect) real time access to everything stored on those servers to various organizations including, but not limited to, the NSA. Lawsuits around this issue are motivated solely by an effort to do away with parallel construction [1] and enable the evidence obtained through such means to be able to be directly used.
Lots of people know this, lots of people also think this is crazy talk. And prior to Snowden, and to a lesser degree Klein, the overwhelming majority fell into the latter camp regarding anything even remotely close to the scope and scale of what the NSA was doing.
https://en.wikipedia.org/wiki/NSA_warrantless_surveillance_(...
Lots of people knew that mass surveillance was likely with the advent of the internet, prior to 641A in 2006.