I would never buy an appliance that requires a third-party server. Google cannot remove the value from a Zigbee or Z-Wave thermostat like this.
The Matter standard[0] (+HomeAssistant) starts to fix this, but almost all "smart" appliances have this flaw. From Lutron, GE, Apple, Amazon (ring), Philips(Hue), Samsung, LG, Control4, Ecobee, ADT, Schneier, Chamberlain, Tapo.
One of many reasons I prefer home automation hardware that uses ZigBee, Z-Wave, or Thread over using WiFi. If it uses WiFi it almost always wants to connect to or worse requires a cloud, where the dedicated home automation network tech is basically the polar opposite and requires that it work entire directly locally or with a local hub.
Other major reason being that "IoT" devices usually have the shittiest WiFi radios that usually don't even support 5 GHz and almost never support WiFi 6/7 modes where they aren't wasting a ton of airtime on their low-bandwidth communication.