Because you are assuming that what happened 50 years ago has an influence on how Trubiskey plays. The Bears have never really had this type of offense with this talent. This in no way resembles the Payton right, Payton lect, Payton up the middle offenses of the 70s and 80s when they didn't need or want a QB.
Don't live in the past, think positive for the future. There are untold possibilities.