A game by absolute freaks, for absolute freaks. If you don't lab kart racers everyday like they're fighting games and try your hardest to complete EVERYTHING in those games, this game is NOT for you.
Almost avant-garde in how little it cares for the casual kart racer audience, forcing you to complete an excruciating tutorial that can take between 30 minutes and 1 hour. To complete one grand prix before you can unlock multiplayer (or use a cheat code). To complete FIVE grand prixes before you can unlock the ability to use old SRB2kart MODS! (or use a cheat code). To stay with one color for your character unless you collect the others, and collect all 82 to unlock time trials. Never has there been a game so obsessed with making players master its mechanics before letting them play with others, as if they were preparing you for real-life war or something.

The game even opens slowly walking you through every option, unlocking each thing in the menu, everything contextualized with Tails and Eggman speaking to you, as Metal Sonic. Clearly, the devs tried to defeat Sonic Robo Blast 2's unnecessarily long intro cutscene, and in their quest for Genesis nostalgiawanking, they made the awful choice of only having the button prompts of the Genesis controller in menus and tutorials, not a huge issue in controller, it is on keyboard, especially because this game just has way too many mechanics and when you finally have to use an obscure one, you gotta press every key or go to the menu to check what key you assigned as the Y Genesis button.

Back to the tutorial, what did they think they were making here, Final Fantasy XVII?? It doesn't even explain things that clearly and there's so much dialogue, no option to reread, just once and trial and error.
It'd be one thing to make a kart racer with a lot of complex mechanics if they all feel cohesive and the races really push you to your limits, like Sonic Riders or even Bomberman Fantasy Race, but I don't think this is it when the mechanics are like 8 different types of boosts, one for each hazard, a charged melee attack? A parry? Two different types of roulettes that by default you have to stop manually???
A lot of this doesn't even come up in the races, it's for the single-player challenges, if it is in the race, you can also probably brute force it and use boost mechanic #54 instead of boost mechanic #301 as originally intended.

There's potential here, but it doesn't feel as good as SRB2kart to be honest. I gave up at the drift section in the tutorial cuz I just couldn't get it to work and the only drift you HAVE to do to proceed is the ultra charged one that gives you max boost #302! If the kart stops moving while you try to drift you instead initiate, you guessed it, another boost mechanic, one that has its own separate dedicated button so why make the drift worse by putting it on that button as well?

I usually don't rank games if I know that they're just not for me or if I played that little, but I don't see how the things I complain about would really do any good to any game in any genre, and even if all players use a save file with everything unlocked, I'll have to stand my ground unless they rework everything.

They tried to make a kart racer with more complex mechanics than Sonic Riders, and thought they had to have THE MOST mechanics to do that. They saw that some Riders players missed mechanics because of the lack of a tutorial and thought they had to overtutorialize EVERYTHING and demanded they mastered the game before even letting them race.
Don't think this will ever catch on and most will probably continue to just play SRB2kart.