Good point. I'd just worry about my device being bricked should they hypothetically go out of business (see other IoT stories). Great, I wouldn't be paying for the software updates anymore, but the device I own would be entirely useless. There's nothing wrong with offering a self-hosting version either, arguably it would be preferable.

I'm applying my personal values here, of course. In practice there will probably be contractual agreements to provide the service for some number of years.