So you're probably wondering how this screenshot exists. Well, my understanding is this: The update to Mario Kart 8 Deluxe has been released in order to prevent server issues when the DLC comes out, however, the DLC itself has NOT been released. But the modding community, being as incredible as they are, have hacked the DLC in, albeit it's only playable through friend rooms. As for the fact that every cup is visible, I believe that the tracks are not yet accessible until the next waves drop, and they just added the cup icons so the menu didn't look weird. Not sure why Ninja Hideaway doesn't have a tour label though. UPDATE: If your copy of the game is on version 2.0.0, you can view the cup and the new tracks, but they are only playable through modded friend rooms.
Screenshot came from this post: twitter.com/Zachruff/status/1504449856047263744?cxt=HHwWgMCtwYrL8OApAAAA Thanks to Scratch for ruining the quality