I think it has more to do with the investment in the programs, but before MAC basketball was on TV it was a much better product. In the late 1980s and through the 1990s and say to 2005 or so there were many NBA players in the MAC. Very rare now.
Its rare to have a MAC player drafted. NBA down to 2 rounds and huge percentage of international players. A US player has to be in the top 30-40 to have any shot at the draft. The MAC back in the day had a lot of respect because of the amount of 8,000 seat arenas in the conference. That in the pre TV days classified the MAC as a major basketball conference over the MAAC (little MAC).