At this point of the season, anything is possible. One of Philadelphia's losses was to Washington. One of Kansas City's losses was to Buffalo, but those were regular season games. With the conference championship on the line, it will come down to who wants it the most.
Washington hasn't been to a Super Bowl since 1992. The Bills haven't been since 1994. The Bills are the only team ever to reach the game four years in a row, but they never won it. One of the losses was to Washington. The only other team to make it to four games without winning one is Minnesota, and those games were not in consecutive years.
I'm with your dad. I'd love to see Buffalo and Washington play for all the marbles. Another week and we'll know which teams will be playing in Super Bowl LIX. Believe it or not, I've watched all 58 of the previous games on television. Yeah, I'm old.
In case anyone is interested, there technically was not a Super Bowl I or Super Bowl II. Those games were simply called AFL-NFL Championship Game for the first two years. That was before the two leagues merged. The merger was announced on June 8, 1966 but the merger did not happen until the 1970 season, the year after Super Bowl III.
Super Bowl III was first game to be called the Super Bowl, before which the New York Jets quarterback Joe Namath boldly predicted this team would beat the (then Baltimore) Colts, who were favored by up to three touchdowns.
Namath carried out his promise, and the game has been called the Super Bowl ever since.