Mario Kart 8 Deluxe 's Version 3.0.1 update, released on November 28, 2023, primarily functions as a stability patch following the major Wave 6 content drop of the Booster Course Pass. Key Update Features

Network Stability: Crucial fixes were applied to prevent "comm-errors" during 12-player regional and global matches. The Turning Point: Wave 6

It is a complex, contradictory string of text. It is simultaneously a theft of intellectual property and a digital time capsule, written in the shorthand of those who refuse to pay the ticket price for the ride.

With the arrival of Update 3.0.0 (and the subsequent patches leading up to it), the game didn't just get a few tweaks—it underwent a complete transformation thanks to the Booster Course Pass.

Summary

When you see "Mario Kart 8 Deluxe Switch NSP XCI - Update 3.0" online, it is simply referring to the base game files (XCI for cartridge dumps, NSP for digital downloads) paired with the necessary NSP update file required to unlock Wave 2 of the DLC and custom track features.