It wasn’t really that strange, people got tailed all the time during the nuclear weapons program and after, to make sure that they weren’t gay. Shit was wild in the early 50s. A senator committed suicide because his son was outed as gay, getting dirt on people was hardcore. People got fired on the flimsiest of claims.
Physical surveillance was pretty bad, even then. Digital surveillance has gotten worse today, but it’s much more fragmented and not so…eerily similar to the CCP. Also, fuck McCarthy. The book on this timeframe is a wild read, highly recommend it as it explains the postwar era and cold War paranoia.