Man, I disagree with you on Starr, assuming you take him and give him modern training, nutrition, being coached in the current systems, etc...Obviously you can't take Bart from 1966 and Marty McFly him 50 years to 2016 and expect he would play. I doubt if Bob Lilly from 1966 could play today, because of course he would weigh between 240 and 260 at defensive tackle. But I don't think that means you say that QB X, Y, or Z of today is better than Bart Starr. Would QB X, Y, or Z be as good if he were born in 1936 as he is right now having been born in 1987?
I will give you this point, however. A Bart type QB today would need commensurate talent as he had in the 1960's around him to win Super Bowls.