of the top 30 to 40 teams would earn more money. But as the fans of the left-out teams might not follow as closely, this closed group model might back-fire. Why not just follow the NFL then instead of this minor league closed league.

But for an individual conference, there still has to be a point of diminishing returns.

If they made a 48 team conference, this multiplier effect can't be much because its just sensory overload for the fans. Too much inventory to care much about other teams' games just because they are in your conference.

What is the magic number? I suspect that more than 16 already is going downwards on the point of diminishing returns for this multiplier effect you are talking about.