If all the staff is doing the job, then when you lose 'star power' you have players developed to take their place.
I find it nearly unfathomable that we could have signed so much WR talent over the past years and have only 1 WR this season who looks like he really knows how to play WR on the major college level. That means we have had no WR development.
And then there is the OL. Games are won in the trenches. If your OL floats from average to downright poor play, your offense is seriously handicapped any time you face a D with major talent and/or good talent with first rate coaching. 3rd year starters often look like RS freshmen starting for the first time. And no depth has been developed.
Are there signs that Searles and Galloway definitely will produce well developed players next year? If so, what are those signs? If Mack sees them, he should make us all aware.
That's just 2 position groups on offense. As you say, "the problem is spread all over." WE have players with experience who play as if they are new to CFB, and we have very little player development, on both sides of the ball and on all position groups.
It is next to impossible to solve all those issues with pep talks for the staff or even by firing both coordinators.
For UNC football, the problem immediately goes to fans. A sizable piece of the UNC football fan base is already at last half checked out for this season. The UNC football fan base has a decades long molding that has produced a crowd that is easily demoralized and just stops watching. People throw up their hands and accept mediocrity because they assume it never can get better.
Mack's successes always have been based on his silver tongue wowing recruits and journalists. Mack charms people to get them to play for him and write for him. Charm can draw top recruits even when the team is losing (unless the losing gets too big) and charm can keep the media at bay a long time. But charm does not make a mediocre OL coach into a master of OL development. Charm does not mean that players on the UNC D will suddenly start tackling well because fundamentals have been taught well, and demanded, by position coaches.