FYI, I'm not remotely as confident about that claim as I was 25 years ago. (I'm the one quoted.) Specifically, I use Signal today and suspect that it's secure against mass surveillance.

But if I were ever targeted individually by a nation-state actor, I presume it would be game over.

Not really; it has been publicly known since the late 80s, with reports like Duncan Campbell's Somebody's Listening (1988)[1]. In 2001, even the European Parliament was telling people to use encryption to avoid the widespread NSA private and economic espionage.

Snowden gave us the details, but it's been generally known for a long time.

[1] http://www.duncancampbell.org/menu/journalism/newstatesman/n...

I remember ECHELON [1] being the talk pre-Snowden, in the 90s and prior.

[1] https://en.wikipedia.org/wiki/ECHELON

Here are a couple examples from 1972 and 1988.

Since the 70s journalism has surfaced the idea about “The Concealment of the State”, pieces touching on covert and surveillance aspects of the national security establishment in developed countries, how the deep state draws power from the national security and intelligence communities, and the idea of “mass secrecy” as a source of power.

I can’t find the reference right now, but seems like this idea was even showing up in Tom Clancy’s popular page turners.

Examples on listening to communications:

Q. So far we've been talking about various kinds of sophisticated electronic intelligence gathering. What about tapping of ground communications?

A. Of course all trans-Atlantic and trans-Pacific telephone calls to or from the U.S. are tapped. Every conversation, personal, commercial, whatever, is automatically intercepted and recorded on tapes. Most of them no one ever listens to, and after being held available for a few weeks, are erased. They'll run a random sort through all the tapes, listening to a certain number to determine if there is anything in them of interest to our government worth holding on to and transcribing. Also, certain telephone conversations are routinely listened to as soon as possible. These will be the ones that are made by people doing an inordinate amount of calling overseas, or are otherwise tapped for special interest.

— David Horowitz (August 1972). "U.S. Electronic Espionage: A Memoir". Ramparts, 11.

// via http://cryptome.org/jya/nsa-elint.htm

Somebody's listening . . .

and they don't give a damn about personal privacy or commercial confidence. Project 415 is a top-secret new global surveillance system. It can tap into a billion calls a year in the UK alone.

They've got it taped

In the booming surveillance industry they spy on whom they wish, when they wish, protected by barriers of secrecy, fortified by billions of pounds worth of high, high technology. Duncan Campbell reports from the United States on the secret Anglo-American plan for a global electronic spy system for the 21st century capable of listening in to most of us most of the time.

— Duncan Campbell (12 August 1988). “Somebody’s Listening”. New Statesman, Cover pp. 10 - 12

// via http://cryptome.org/jya/echelon-dc.htm

TBH, I didn't even know they existed back then.