I would add...
'and the vast majority of americans dont understand why they should care about government surveillance and how that relates to installing an internet-connected microphone in their home'
unfortunately most of us in the hn crowd probably feel like there is tons of awareness about surveillance right now, but my guess is that feeling is the result of filter bubbles.
When we start to talk about government surveillance I think people go over board and start looking at IOT devices over aggressively. It not hard to bug a house, people are usually gone for at least 8 hours a day on weekdays. If I was doing an ops, it be easier to break into their Wi-Fi and infect a device that way or break into their house and just plant a bug or two rather than wait and get a warrant for their data from Google or Amazon which is time consuming and filled with paper pushing, plus the added fact that Google and Amazon have both pushed back in recent years in court battles.
When it comes to "Big Brother" you are fighting a rather big monster with zero days, money and time on its side. Even as someone with enterprise grade networking equipment in his house and a security background, I just know its a time game if you fighting the "MAN". I had a friend that was super paranoid. Enterprise gear, no IOT, custom linux router with live patching, some pretty cool stuff. Asked me to pentest him. A door left unlocked (planned to use a bump key) by his wife before leaving the house and a PoisonTap attack on a windows computer and he was pawned. GAME OVER.
You would probably need to edit your question to "Why do you think millions of people bought an [Amazon] Echo Dot or a Google Home [Mini]" The evidence is clear both are the lowest costing home assistant device for their respective lines. At $30 on sales this season it could make it even into many gift swaps with that budget. Just as a few years ago the Firestick and Chromecast did.