The argument isn't so much that Dak isn't top 10 as it is that there aren't but about 10 really good quarterbacks in the league, many of which are buoyed by a stout defense, or the quarterback running all the time (which isn't really a quarterback element, more an adjunct to throwing the ball) and being as quick as any of the defensive players.
There have been many other quarterbacks who were far worse and won Super Bowls, as in P. Manning in his last "win". Or Rothesliberger in one of his SB wins. John Elway was lauded to the skies for years but lost 4 SBs before a 2,000 yard running back came along, matched with two top-10 defenses. Was it all Elway's fault he lost 4 SBs? Jim Kelly had a massively talented team for years, couldn't win a single SB. Guess he sucked as well, funny how he is in the HOF.
Add to that list Moon, Fouts, Marino and Tarkenton, among others. None of them won a SB, yet all are HOF quarterbacks.
Blaming Dak for the Cowboys' ills is taking the easy way out...