I want a law that requires publishing your API for apps like this as well as allowing users to crate their own frontend based on it. That would enable more privacy aware versions of these apps.
I'm not trying to suggest that these sorts of things should be this way, but if there is a server involved in the economics of maintaining that endpoint come into play and can't be ignored. Ideally things were federated and you could point your car or whatever device at and endpoint you maintain, but that comes at a cost as well as maintaining software where both client and server are controlled by the same party is an order of magnitude easier than cases where they aren't the same.