I thing being continuously updated should be tied to receiving new external content.

It's fine to have an embedded device that's never updated, but never receives new content - it doesn't matter that a system won't be able to show a new emoji because it doesn't have any content that uses that new emoji.

However, if it is expected to display new and updated content from the internet, then the system itself has to be able to get updated and actually get updated, there's no acceptable excuses for that - if it's going to pull new content, it must also pull new updates for itself.