The NFL, particularly the AFC is littered with these kinds of stories over the years (decades).
Raiders in the 70s were fantastic, but Miami & Pittsburgh
Cleveland in the 80s, but Denver, Cincy
Colts, Steelers in the 2000s/2010s, but New England
Bills presently, but Chiefs
Going forward, who knows. The AFC is really tough, and typically a few playoff teams don't even make the playoffs the following season. Lots of "what-ifs" ahead for many teams.