I'm always fascinated by the talking past. It's like something in a stage play, where one guy thinks the conversation is about their boss and the other thinks it is about a pet cat. "Makes all these demands!" "Yes!" "Won't use the catbox!" "Yes! ...err, what?"
When the HB de jour touches on something interesting, we talk about that -- the technology, the history, the underlying science. When they don't say anything interesting, we get distracted -- then it's Monty Python, book reviews, whatever. From our point of view it is all equally interesting.
For them, the conversation is entirely adversarial. Every single word is an attempt to score debating points. So if we talk about related aspects of the technology we are evading. If we talk about Doctor Who we are trying to distract.
They don't just misread the conversation; they misread the venue. They see themselves as a brave investigator going up against a cadre of trained disinfo agents in a quixotic quest to awaken the few stubbornly ignorant innocents that may be there. Everything matters, every word matters, and of course everything is dead serious.