2005 Steelers. 2007 Giants. 2011 Giants. 2020 Buccaneers.
In the past 16 seasons, four teams (that's 1/4 or 25% for you math nerds, haha) have won the Super Bowl as a road Wild Card team (and/or after barely squeaking into the playoffs). The '05 Steelers, '07 Giants, and '20 Bucs all won three games on the road en route to the Super Bowl. (The '11 Giants hosted their Wild Card game after coming away with a someone-had-to-win-it division title at 9-7, but had to win on the road thereafter.)
Ultimately, maybe this is how the Bills will win a Super Bowl one of these years. After all, over the past 16 years, there's a 25% chance that the winner will take this route.
If the Bills do take the "us against the world"/underdog mentality and ride it to a Super Bowl win when no one is expecting it (which I think suits this team's DNA very well, by the way), would you still crave a season where they do get homefield advantage, win two games at home, and then win the Lombardi, or would you be satisfied by the out-of-nowhere win?