Pretty sure you should read it again. His corner was his one refuse where he figured he wasn't being watched (but never knew). He assumed one day he would die for what he did in that corner, which was just write down thoughts on paper. He also had to be aware of people that existed inside and outside of his social circles, because they themselves were a part of the monitoring. Remember his neighbor kids? He also was very afraid of his lifestyle choies including the prostitutes you mention. Re-rad the excerpts of how he flirted with his lover over months and how afraid they were to hold hands or show affection because of the monitoring.

The key here isn't the technology, but the general paranoia of everyone and everything around you belonging to a society of oppression and absolute control. That, in total, was the point. Not just some dumb device that could potentially be compromised if someone wanted to, but that all devices are what we would consider compromised because everyone wanted to partake in the surveillance.