This technology has been around for nearly 10-15 years. It was initially an FBI/CIA tool that has finally become so easy to implement that they can build it into a standard high end WiFi router for motion detection. In the military version of this, they can actually make usable images of the people in the room. The higher the WiFi frequency, the better the image (shorter wavelengths for showing smaller features).
Nearly all ISPs are trying to find ways to monetize the data that they collect about their customers, including DNS queries (when you type a web address, they read it and same for doing searches that are not https). Similar things are happening with cars equipped with OnStar and other communication systems - even if you don't have an account with them. The auto industry has already been caught selling user data to auto insurance companies. And the same for apps on your cellphones. Especially if they are free. They are making money somehow, and it could be simply selling your data and location / travel info to insurance companies and other companies that can profit from your data.
And smart TVs? Oh my. Not a good idea. At all. Several of them have been caught send viewer data back to the mothership. Was it Vizio that the first one caught? And on this same topic, the US FCC is considering allowing the new ATSC 3.0 TV tuners to allow providers to charge for over the air TV broadcasts. To make money.
I have a zero trust policy for my ISP, so I use my own gateway equipment and use my own WiFi with a hardware firewall (don't rely on your end devices to firewall). For devices that stream, like cellphones, TVs, and Rokus, I have them on their own DMZ network (with NAT) that does not have access to my house protected network. And I have also made Cloudflare my DNS provider - not just let the ISP supply DNS web address data. Because they make money off your DNS queries. I saw the effect of this instantly one evening while watching TV with my girlfriend. She did a search for adopting cats, and a few mniutes later we started seeing cat food commercials - over and over. Dystopian.
Since we just decimated the US government agencies that protected US citizens privacy, this protection has been nearly ruined and a vacuum exists. So plan for your devices being used against you - anytime money can be made. I used to think Edward Snowden was a bit off, but not since the ... 2016 US election. Just sayin'.