I really like the data - to see how weather and my activity influences temperature, air quality, network... I can absolutely see, just in the temperature data, when I get out of bed; air quality shows when I cook, exercise, open windows. Nobody who's not me needs that data, so all the sensors plug into an RPi or, at most, connect through zigbee/bluetooth. I can't even imagine what They can infer from Smart TV or wifi refrigerator, and cameras can fuck right off.

But I can see where, if you like the data but can't figure out how to manage it yourself, cloud devices could seem pretty attractive. Techno-magic and fun to be part of, and there's so many people saying that privacy just doesn't exist anymore. Probably people with an IoT security camera in their bedroom.