He problem isn't that people won't watch more football, it's that there isn't enough talent.
The idea that people want to watch a bunch of dudes who aren't good enough for the NFL is not very bright. It's like trying to have AA baseball survive independent of the MKB affiliate team. The money isn't there to watch dudes who can't be a 3rd stringer in the NFL play.
Other sports have young prospects coming up through their minor leagues. Football you go college to NFL, there's no need for a middle level.