The Switch version of Mario Kart 8 ended up adding an entire game's worth of extra DLC courses, which is kinda nuts. Especially considering how they started adding this stuff 5 years after the game came out (2022 vs 2017) which was an entire 8 years after the Wii U game came out. This adds 48 tracks (yes, 48, as many tracks as the main game). These are a mix of real-world "touring" tracks taken from the Kart phone game, retro tracks from other Karts, and some entirely brand-new tracks (usually one or two for every wave).
Basically, this was a Mario Kart 9 in everything except name, and it got a staggered release like FFIV: The After Years. Now that we have Mario Kart World, I guess this pack is Mario Kart 8.5. Which begs the question of why they didn't just put this out as a new game and rake in coin. They could have easily sold this for $50 (instead of the $25 total that it costs), plus an actual release would have gotten some fanfare and people like me wouldn't have forgotten it existed, so it would have sold a lot better as well.
So how is it? Well, right off the bat, they missed a big opportunity by not having this add Booster from Mario RPG as a playable character. This caused them to lose out on numerous potential sales from Booster-enthusiasts and Booster-maniacs the world over.
Alright, here we go, 48 (Jesus) new tracks over 12 (Jesus) new cups. I better pack a lunch, this is gonna take a while.