Offense wins games. Defense wins championships.
That is an old trope in the world of football. You will here a few times every single single season if you watch, listen, or read football related analysis or coverage. Running into this maxim is inevitable.
Despite the lip service though, most of the emphasis of this league is put on having a lights out offense, specifically an elite quarterback. That theory still seems to be holding water, as the team led by big name quarterbacks like Tom Brady, Russell Wilson, Aaron Rodgers, and Ben Roethlisberger are all in the playoffs right now.