Dak has not asked for more money than anyone else in the league, first of all. And MOST teams win with less than elite quarterbacks. Eagles won with Foles, but is Foles "elite"?
Hardly. Was Flacco? He "won" a Super Bowl. But no he's not elite. Rodgers and Brees are widely considered elite, but each, despite many great individual seasons, have only won 1. Either could get another one this year, but Brees is very likely to be in his last year, so he can win at most 2. Aikman won 3, but there are some who say he doesn't even belong in the HOF, was he really elite? Wilson has won a SB and should have won another one, but both of those years he had the number one defense in the league.
Of course Brady has 6 rings, no doubt he's elite, that isn't debatable to any great degree. So having the elite quarterback is helpful.
It comes down do you want to get someone other than Dak to be the quarterback, taking the risk whoever you get turns out to be Brady or Wilson or Rodgers, and not Young, Leaf. Lineart or Quinn, or do you try to build a complete team around Dak and win a SB with the "bus driver" quarterback like Johnson or Dilfer?
Both approaches have worked.
You pays your money and makes your choice, and hopes like heck it works out....