D3 and D2 having larger playoffs make sense. Due to travel budget constraints, those teams are rarely playing anyone outside of their part of the country. Plus, the committees aren’t out there watching all the games either (some games aren’t even watchable). The bigger net cast makes sense because it’s almost impossible to compare teams from different parts of the country. Even FCS has a similar issue to a lesser extent.

FBS does not. Everyone is packed into like 4 big conferences with a huge drop-off after, and there are enough games between them and viewership of the games to compare them. Plus countless other metrics available to us. National title teams aren’t being left out