I'm mean Culpepper, kind of was, and then his knee exploded and Bridgewater may have been that guy and almost lost his leg.
But other than them in my 20+ years as a fan it's been mostly older vet stopgaps (Moon, Cunningham, George, Favre) average* guys (Cousins, Johnson x2, Cassel, Bradford), and draft busts (Jackson, Ponder, Bridgewater**). Even if you go back further and include every year post-Tarkenton it's been the same thing pretty much.
*Not to mention the fill ins (Bouman, Wynn, Frerotte x2, Holcomb, Bollinger, Webb, Freeman, Keenum)
**injury "bust"
I just named 21 different starting QBs since 1996, 23 if you count the Johnson and Frerotte reduxs as 'different'.