Mr.Olympia 2024 Men's Classic has always been popular... I think you're coming to this topic through social media and not because of the very essence of Mr. Olympia.
Popular? I kind of doubt it, they claim anticipating a record 120 000 attendance for a 7 days event, it's a pretty low number!
Also, no viewership statistics, so no, doubt it can beat an NBA game!
I'm going to quote myself completely because otherwise my idea loses its meaning.
Mr.Olympia 2024 Men's Classic has always been popular... I think you're coming to this topic through social media and not because of the very essence of Mr. Olympia.
First of all, you're mentioning a lower category, I mean if you mention Men's Classic, since the main event is the Open, and the guy you name has been stuck there, but more for money reasons.
Currently I consider this sport to be shit, full of steroids and needles everywhere, it always has been, but today social media and mainly the guy you name are the main influences for guys to end up dead at 35 years old, or less.
First of all, what is popular for you, millions of fans watching some guys play or practice it, on the other hand, you surely don't know that fitness is currently one of the niches with the most followers not because they see a guy in a swimsuit, it's because his followers practice it, then I mention social networks, because that exact guy that OP mentions, is even more followed than the winner of the main event the OPEN.
Then you can't compare apples with pears in terms of audience, it's obvious that an event like the NBA has followers, but that fact in itself doesn't make other sports less popular, you get the point. (imo)