I have no earthly idea how Campbell will do. I'm sure he's competent at worst. And I have no doubt that Holmes will do well. The issue will be to take a multi-decade losing franchise and to transform them into winners. Tough to do.
The rub is the time and support given by the owner for both GM and HC. If they get the time (3 or 4 years) they may get it going... may. Not many owners stick with guys that long. A lot has to go right.
The other interesting issue is Goff. He's not going to have the Rams offensive teammates to help him. He's going to have to perform with less than adequate talent.... which means the likelihood of success for a very expensive QB that is on a short leash is small.
Probably the Lions will be picking top 5 or 6 in the 2022 NFL draft, and Detroit will make a change to a cheaper QB option.... again, unless Goff takes some huge leap that is difficult to see given his supporting cast.
Going to be some more rocky years in Detroit.