I have been arguing for years that looking at total offense is stupid and lazy, especially as it pertains to Iowa's offense. Their limited # of possessions and emphasis on protecting the defense and playing the field position game will always make total yards/game look much worse than their offense actually is. Offensive efficiency is a much better metric, and in their good years, Iowa is around top 1/3 or top 1/2 of the country in offensive efficiency metrics.
In BF's first year, they were 44th in the country (better than the previous year under Davis, 57th).
In 2018, they were 41st. Things didn't look too bad.
In 2019, they were 53rd, but they were way lower than that prior to the bowl game vs. USC (that single game moved them up about 15 spots).
In 2020, they were 64th.
In 2021, they were 90th.
There are no numbers yet published in 2022, but it is safe to say that however many FBS teams there are, that will be Iowa's ranking.
I was reserving judgement on the BF-hire until things played out...they have now played out, and then some.