As stated originally, it's likely that making a mid season change could make things worse.
By Poisonut on 07:37:22 09/14/21
[In reply to "The crime is having the worst D in OSU history last year and no progress so far this year" by the Displaced Buckeye, posted at 07:26:09 09/14/21]
you're assuming changes can be coached up to a point in season that things can get fixed. (Extremely difficult when each week your putting in an exorbitant amount of time installing game specific game plans each week).
You're assuming there's someone qualified or able to improve the level of play calling/scheming on the staff, and that they'll buy into taking that position which is one with the cards stacked against you.
There's a reason coaches especially coordinators are not often fired in season, and that's because it's rarely fruitful.