My Nest (2014) is working perfectly fine but I'm required to pay for a new model.
Apparently, heating and cooling a three-bedroom home requires more advanced technology...
I am in the same boat, but apparently it will continue to work. Downside is no more remote control. Editing the schedule via the thermostat is really going to be the real pain point. Though the app/website stopped working for me 6 or more months ago anyway, only the google home app still worked for basic temperature set.