Nintendo recently announced a new slate of downloadable content for Mario Kart 8 Deluxe in the form of 48 tracks from earlier entries in the series. The Booster Course Pass is set to be released over a two-year period, concluding at the end of 2023. Expanding the content of the existing game is a great value addition for players, but it comes years too late. Mario Kart 8 Deluxe was released in 2017. Waiting five years before adding content to a game is an odd choice, especially when that content is being released over another two years. This leaves players ponying up cash for additional content in a game made to be cutting-edge years ago.
To make matters worse, the "Deluxe" in Mario Kart 8 Deluxe is part of the game's nature as a port of a 2014 Wii U game. It's a great game, and it made sense at the time for Nintendo to want to give more players a chance to see it. However, doubling down on it now means Nintendo is developing content for an eight-year-old game that will have been out for nearly a decade by the time it's done updating it.
Arguably, the same can be said for Super Smash Bros. Ultimate, which released in 2018 and received updates in content through the end of 2021. But that was a three-year period, and more importantly, it was a game designed from the ground-up for the Switch. Nintendo has released a Mario Kart game for each of its consoles since the series' inception, and it's bizarre to think the massively successful Switch would be an exception. A Mario Kart game designed for it specifically would sell incredibly well, especially since it could take advantage of the console's portable nature. Players don't need many buttons to play Mario Kart, and while a Joy-Con turned sideways is a little awkward, it's still enough to warrant a console-specific game.
Mario Kart 8 Deluxe does makes use of the Switch's features without having been built for them. However, game design is about pushing forward and innovating. Nintendo has delivered tremendous new installments of Zelda and Mario for the Switch with Breath of the Wild and Super Mario Odyssey. The console has shown time and time again its potential as a fresh reboot for games that suffered under the Wii U era. Ports of games that didn't get the chance to flourish there are fine, but they shouldn't be replacements for new games.
The introduction of old courses from previous entries in the series is also missing out on one of the biggest things that could have been included in a Mario Kart 9: new courses. Super Mario Odyssey had over a dozen new kingdoms for players to explore. Huge kingdoms like Sand or Moon Kingdom offer plenty of opportunities for amazing new courses, and even a smaller world like Ruined Kingdom would let players drive around and avoid its massive dragon overlord. Odyssey is filled with huge worlds filled with verticality and incredibly detailed game design. Adapting them to Mario Kart would be new, fresh and by many standards better than any old courses Nintendo is planning to bring back.
Above all else, Mario Kart should have new mechanics by now. Each game in the series hasn't added much or been revolutionary, but the slow accrual and polishing of mechanics over the years is what resulted in the success of Mario Kart 8 Deluxe. Refusing to move forward for an entire decade in favor of releasing DLC for a port comes off as an oddly lazy move from Nintendo, a company that has historically gone great lengths to give players value for their time in other releases. While it's certainly not a perfect company but making another Mario Kart game for Switch is a very low bar for Nintendo to miss, and while a Mario Kart 9 might be in the works, the Booster Course Pass' announcement means a true sequel is farther away than expected.