The teams that are allowed to play in the CFP are or are becoming national all-star teams. How many 5 star recruits are leaving CA and TX and heading to Alabama, Clemson, OSU, ND, and Oklahoma because they are the only teams that get to play for the championship every year? Sure these teams have been recruiting well for years but look where they are coming from now. I can point to 4 or 5 guys on Bama and Clemson that are from California and absolutely would have signed with USC or Pac12 teams 5-10 years ago. But they didn't. They want to play for a National Championship so they contacted these elite teams and asked their coaches if they would be interested (see DJ Uiagalelei).
The bias of the CFP committee is going to kill the sport unless it expands or changes something.