Lets not forget that baskeball is not a real sport.
As far as worldwide popularity, its even less popular than bodybuilding.
The countries that don't follow b-ball don't count. What counts more is how much money is made and generated. Muscle man shows may be more popular worldwide, though I doubt it and would need proof other than your word, but b-ball makes a lot of people very rich and allows even more to make a very good living. Just the tank-tops sales alone trumps anything bbing can deliver.