Open source would be ideal but I imagine the reality of NDAs and proprietary bits and other lawyer stuff means most companies won't or can't. Which, fine, but if you cut off services for a cloud encumbered device in a way that will effectively brick it, you should at least be required to push a final update that lets it continue with whatever basic functionality is reasonable. None of this "we reserve the right for this thing to stop working arbitrarily when we feel like it" in the ToS, the maker is legally obligated to make it keep working if you ship a product like this.

It's an unrealistic pipedream, but one can hope.