That's like telling me to not read sequels to books.

Just because it shares mechanics and characters does not make it the same game.

What a silly statement. There are tons of new features, characters, and courses in World.

For better or for worse, it's actually quite different. Many people seem to actually prefer Mario Kart 8 lol

It's different to the point I sometimes go back to 8 for the more traditional format. That isn't something that has ever been the case for me across other mario kart games.