Miami was 66th in the nation in rushing offense in 2020. 163 yards per game. That's middle of the pack, not great but nowhere near atrocious.
In 2021, through 6 games, they were averaging 160.3 yards per game rushing. Once again, not great but decent. Cam Harris got hurt in the 6th game against UNC. The rest of the season with no Harris or Chaney, they only averaged 97.2 yards per game. Same scheme, same line. Good running backs find a way to get yards even if the line isn't opening holes for them every down. Yeah, the line sucked but every other running back was able to average over 4 yards per carry besides Knighton.