@firefoxwebdevs I think it's less about use cases and more about general trust, as privacy often boils down to. If you're talking about an AI "kill switch", you're talking about trust in what's been defined as "AI", and trust in the browser developer as a whole.
Once definitions are murky, there's an area open for ongoing redefinition. One way to adopt a "private by default" approach is to follow what cookies do, for instance, and allow users to allow limits to the extents of permissions.