I thought Super Mario Kart was an okay game. I wouldn't put it in my personal top 10 or even top 20 games of all time, but it would be somewhere in the top 50 (though it would be in my top 20 SNES games). I think it was an innovative game but imo it's gotten a bit dated. Mario Kart 64 was a lot better to me; in fact, it's my favorite racing game of all time.
Back on the main topic, another horrible SNES game is Advanced Dungeons & Dragons: Eye Of The Beholder. It's a point and click game that's very slow and boring.
Drakken is pretty bad too. I had it back in the day, and after giving it an hour, I didn't get that far, and the game never gave me any interest towards trying.