It's normal for college football. The problem is the last decade has taught us to think the good teams will be good until eternity. You can't hit on every prospect, people don't pan out. Outside of Alabama, Clemson, and maaaybe Ohio State, every other team that has ever been part of the college football national championship conversation the last decade have had 3 and 4 loss seasons.
They usually end the same way, really good players masking serious problems that don't get addressed because the team performs well. But then those guys leave and it hits like a ton of bricks.
Yup. See FSU and Crab Legs/Dalvin Cook.