I hate this type of reasoning.
Let's apply it to the defense instead: McDermott is a mastermind. A gem. "Best Bills coach ever" (LOL but ok). So let's make due with so-so defensive players on dirt cheap contracts and give Allen weapons on offense.
SF gets to the SB and wins tons of games without a real QB because of skill players. Imagine in SF had a real QB?
Brady got a couple Super Bowls with mostly elite defensive play, but overall didn't win without elite playmakers either. Edelman and Gronk were pretty damn elite, as were the guys in TB (Evans, Godwin, Gronk).