There is a big difference between being a boxing star and a crossover PPV star.
At the moment GGG is a big BOXING STAR. He can fill a 20k arena no problem at all, because boxing fans especially in areas like NY, LA and Vegas love his style of fighting.
It will take a little time to be a crossover PPV star, but this is a solid start. Some were predicting in the 250k range, but that was ambitious. 150k is respectable considering it was his first time headlining a PPV event.
Fight Hype were the first to report the numbers and it seems to be consistent with what others have heard.
This means it is likely that The Big Drama Show will stay on PPV going forward as long as he can get good marketable opponents.