Most other leagues don’t call their own championships/titles the “world” anything. American Major League Baseball explicitly calls its finals the World Series. The American NBA calls its winners the World Champions.
For those two sports and leagues, it’s a pretty solid argument that those are the best players and coaches in the world at those sports, where the American leagues attract the absolute best talent.
It’s harder to make that argument for soccer leagues around the world, though.
Most other leagues don’t call their own championships/titles the “world” anything. American Major League Baseball explicitly calls its finals the World Series. The American NBA calls its winners the World Champions.
For those two sports and leagues, it’s a pretty solid argument that those are the best players and coaches in the world at those sports, where the American leagues attract the absolute best talent.
It’s harder to make that argument for soccer leagues around the world, though.