Most of the privacy issues with smart appliances has to do with the apps that you're required to use to access the smart features. The cell phone apps harvest

Most of the privacy issues with smart appliances has to do with the apps that you're required to use to access the smart features. The cell phone apps harvest data. Not so much on the actual appliance. There are also issues with the apps having malware bundled in them. They're just bad apps, generally. The appliances do get hacked though. It's not unusual for IoT devices to be used in ddos attacks. Really, this is just a good reason that everyone should be using, at least, router level DNS filtering to disable a lot of this stuff. One can go a lot further but that's a good start.