TOP COMMENTS FROM VIDEO BELOW
The NFL crushed the NBA because the NFL has crushed sports viewership for 2 generations. MLB declined (though stabilized), NHL steadily got more popular but it’s a highly regional sport internationally, and the NBA peaked in the MJ/Kobe eras. The ONLY constant is that the NFL has smoked viewership in the US for decades.
Roster turnover is a major problem. Rivalries are non existent because star players leave their team every other year.