This is something that bothers me as well, implementation decisions are what drives this a lot. I have a nest thermostat and it seems like the app decides to log me out randomly every once in a while and I have to go through the whole login/2fa process, sometimes in the middle of the night when trying to adjust the temp! There is no need for internet connected thermostat most of the time, I would much prefer Bluetooth with no login needed ever.

Why have such a thing ad why tolerate it - I mean get rid of it or tell whoever owns it now to fix it. What is the value of these things?

it came with the house and I haven't got around to replacing it yet, nor should I have to really.

I really wish that all thermostats at least had the option for local control. z-wave and other standards for this aren't even new.

My Tesla Model 3 _can_ remote start the air conditioner via the cellular network, but it can also work via bluetooth if I'm within maybe 20 to 30 meters of the vehicle.

Of course, Tesla is also more friendly than these others and makes the service free.

I'm only familiar with the systems where the fob is still just a proprietary remote. It also has a phone app, and that's what costs extra. The fees are too high, but the existence of a fee is sensible.