While it does not add new characters or tracks, this update focuses on improving the online experience for specific DLC courses:
This patch directly follows the major update, which added significant features that are still central to the game today:
Introduced the ability to toggle specific items on or off in offline VS races and certain online modes. Mario Kart 8 Deluxe Switch NSP [Update 2.2.1] (...
Improved invincibility time after crashes based on the driver/vehicle combination and ensured gliders remain open even if struck by lightning while in the air. Technical Information (NSP/XCI)
Fixed an issue where the image would become "choppy" or experience frame rate drops during online play on this track. While it does not add new characters or
Corrected a bug where Lakitu would drop players in the wrong location after they fell off the track. Context: The Wave 3 Foundation
Added two cups (Rock Cup and Moon Cup) featuring eight courses like Maple Treeway and 3DS Rainbow Road. Corrected a bug where Lakitu would drop players
For users utilizing digital backups (NSP/XCI), this update is essential for maintaining compatibility with the latest online lobbies and DLC packs.