They still had a terrific QB. But yes, they played a much different style than the Pats or Broncos.
Tyrod was lousy because he got worse every year he played statistically and visibly. If 2015 was his baseline, he'd probably still be a Bill. Unfortunately, it proved to be an anomaly. Kirk's tape is much better than TT's.
Ultimately, Tyrod is a QB that your OC schemes to hide. Rivers and Cousins are QB's that your OC schemes as a guy in the offense who can put the team on his back.
And the "average at best" receivers meme needs to die. TT's top 3 WR's in his first two years are currently all in the top 32 of AAV WR contracts. He had a really good unit, 2017 not included.