Had something pop up, not sure if it's a bug or I messed up when making my database.
I made a new database with a single fed and set up the game to populate a single division of fighters through a few months of in-game simming. Now I'm a couple years down the road and the champion of the game seems to be capped at low level national popularity. I ran him on a title defense that got him about +6 popularity in the US (to get him to 33% nat) and then his next fight he got no popularity at all. He was still getting popularity in the other regions however since he was still high level regional in them (I have a single PPV network set to the highest level in every region in the game, for fun).
My popularity just went up from mid regional to high regional in the US, and is mid regional everywhere else. Is there something I could've missed when making this database that could limit the popularity of fighters? Dude's got 60 marketing by the way, if that matters.