I’m not sure why you think that we’ve “run the ball well”. Take away Breece’s two big runs, and he carried 18 times for 49 yards. That’s 2.72 ypc, and distinctly not a consistently good rushing attack.
And that’s generally been par for the course for his season—big runs buff up the small holes the OL has opened otherwise.
If you want an answer for that, I’m pretty sure that the simple fact that two of our best three linemen are out has something to do with both the running and passing issues—especially the latter.
Oh, and the fact that by far our single most experienced wide receiver returning, Tarique Milton, has been hurt is a huge factor too. At this stage, he and Xavier Hutchinson would complement one another well.
That’s how the running game works. Chip away at them, then break off big runs. If you took away a RBs big plays and they were still averaging 5 YPC, they’d be averaging a stupid amount like 10+ YPC in total.