I completely disagree. As a preliminary matter, if any running back should have his number retired, it should be Jim Taylor.
The fact is the Packers have too rich a history to retire every great player. If the Packers retired the numbers of all their great players, the Packers would run out of numbers.
The Packers have 20 players in the Hall of Fame, but only the five have their numbers retired. A player should not have his number retired unless his name is in the conversation of all time NFL greats at their position. Don Hutson, Bart Starr, Ray Nitschke, Reggie White: these guys make the cut. (Tony Canadeao is something of a special case, because he played in the earlier years of the NFL.)
Favre is a tweener who I would keep out for his poor play in in big games, but will probably see his number retired eventually.
Paul Hornung does not make the cut.