According to PSE the majority of fans in their study want Orchard Park, open air. Not a vocal minority at all.
Pegula also prefers that and said so early in his tenure as owner.
Also, winter weather does not stop the passing game.
Tom Brady, Brett Favre, Aaron Rodgers. All cold weather QBs playing in weather as bad or worse than Buffalo.
Then there was the high flying Bills offense in the 90s. Cold and snow didn't stop a 51-3 beatdown of the Raiders in the AFC title game in Orchard Park.
Football belongs outdoors, and the idea that it disadvantages the passing game on any kind of consistent basis is demonstrably false. The Bills hardly ever play snow games at home anyway.
It's not about a competitive advantage. It's about the fact that domes suck.