If my choices are a z-wave/zigbee thermostat that connects to my HomeAssistant instance and a Raspberry Pi that I have to maintain, I’ll pick the z-wave one (and I did, 10 years ago. It’s been rock solid.)

For my smart devices I prefer devices that can’t send information over the internet no matter what. I don’t want to worry about my thermostat mining bitcoin for some dude in China.

The ones that support HomeKit do record to the cloud, but it’s at least encrypted. There’s failure points, so it’s not a fool-proof system, but it’s considerably better system than most cloud camera systems that will joyfully hand over your videos to the police without a warrant or store it in some S3 bucket that doesn’t even have user level access controls.