I might agree with you if Donovan had recruited those kids and they still performed at a subpar level, but he is just completed his second year with them under at least two and possibly three OCs who required different blocking schemes.
I might agree with you if, despite what I said above, the line had NOT shown any signs of improvement......but they did, to the extent that NU had the second best run offense in the B1G.
Nothing I've said implies that the Oline has arrived. Far from it. But if you can't see the improvement to the line that Donovan has brought, you either are unreasonable or you have an agenda.