...P4 programs in total offense is, in your words "well above average". That is the bottom half of all the P4 schools.
3rd Down Conversion Efficiency - 61st out of 68, absolutely awful
Rushing Offense - 35th out of 68 - bottom half of P4 - your words again, not "well above average"
Passing Offense - 34th out of 68 - not "well above average"
Passing Efficiency Offense - 32 out of 68 - again, not "well above average"
Red Zone Offense - 27th - average Middle third, aka average again
Scoring Offense - 26th out of 68 - average again
First Downs - 26th - average
In short, absolutely nothing about BYU's offense say they were anything but average at best, with one of the worst 3rd down conversion rated among the P4, which is highly concerning.