I think Holly provided exactly what TN needed in her first two years - a calming transition from Pat's early departure and moderate success on the court. If she had then gracefully given way to an outside hire, she would hold a place of high honor in the annals of TN basketball for managing an extremely difficult situation with grace and competence. But it now appears to be the longer she coaches, the more her inability to lead a top flight program gets exposed.
She has repeatedly said she stresses defense, but TN is not a great defensive team - they have good players and height and athleticism, but their defensive system is rudimentary and their help defense is frequently abysmal - it doesn't get exposed badly by mediocre teams, but it is not good enough to get them to the FF.
On the other side, the offense has been a hot mess - it is difficult to see any concepts being taught, or players being developed beyond the natural maturation of age, and no discernible system being run. Even the simple things of setting picks and using them efficiently seem to have gone from the TN game. Pat was not a brilliant offensive tactician, but she drilled the basics, and she demanded disciplined use of them. Holly doesn't seem to even do that. Simmons, Massingale, and now DD seem to have more control of what happens on the floor than she does. And she also appears to have no feel for the flow of the game in front of her - often substituting as if by rota, rather than allowing good flow and hot players to continue to play. There seems to almost be a randomness to her game management. And based on her post game comments, she doesn't seem to understand why things work sometimes and don't at others, or how to promote the good things and prevent the bad things from happening.
Recruiting is a mystery, and TN has the 'storied program', good facilities, and a great fan base going for it, but honestly, based on the product on the floor, I do not know why top national players would choose to sign with the current staff. Local talent I understand, but folks from far away without a personal connection?