The only way it could become the "best league in the world" is if the Saudi investment fund nationalizes all of the clubs in the league and then they proceed to buy like the 300 best players in the world. Then they would need to ship in fans from all areas of the planet and have massive TV deals. This is all before viewing the actual product on the pitch, which could just end up being glorified, super expensive friendlies between mercenaries playing in front of their slave masters in the dessert heat.
I think some of these guys are going to wake up one day and say, shit, I made a lot of money, but I really fucking hate it here. Other than the Muslim players of course, who are now making profit cuz they believe in the Prophet.
Whatever the case, I'll just stick with MLS and never watch a single match of that mercenary league.