If you have a 1st or 2nd Generation thermostat it's still sending data to Google

[NXR]

You can't access it or control it but they are still scarfing your data: **** 

Kill that Wi-Fi configuration on the thermostat itself if you don't like this.

From the article:
In a statement to The Verge, Google spokesperson Laura Breen says users “who prefer to stop providing these logs can simply disconnect their device from Wi-Fi” by accessing the option in the on-device settings menu. “Diagnostic logs, which are not tied to a specific user account, will continue to be sent to Google for service and issue tracking,” Breen says.

[LRS]

Every 7 minutes in my network it turns out, every day, all the time. I have blocked them but honestly if you don't have an option to do so, why keep it on wifi at all? You provide the people who just spat in your face with something to drink.

[NXR]

Nice last sentence phrasing. I may steal that. 😎

Apparently the person in that article developed a way to retain remote control but that won't be an option for most people. Also, if someone had a "professional" install the thermostat they may have no idea how to disconnect it from the Internet.

I agree, but even though I worked in cybersecurity before I retired this was not on my radar. Commercially, when a company discontinued a service they killed all of their infrastructure. 

I have the thermostat presence sensing turned off so now I'm wondering if it's still sending that data. Because with the 4th Generation the Farsight feature uses motion detection even if Presence Sensing is not used for other purposes.