99% of apps on Apple TV have the same kind of login option. If they don’t, it’s on the app developer to implement.
The exception to this that I run into regularly is connecting to a local media server, say through Infuse (seems to handle some codecs better than Plex, and has few if any audio sync issues, though I recommend pointing Infuse at a Jellyfin instance so your library’s metadata doesn’t get cleared and need to be re-indexed on the Apple TV somewhat regularly).
Maybe you ought to take the stance of not talking about something you’re unfamiliar with. Every thing you’ve pointed at has been wrong.