If the league is totally different then why is it that, to this day, half of what I see on TV during an NFL game was invented by Tom Landry?
That includes passing from the shotgun, the 4-3 defense. offensive pre-snap motion, and even scouting opponent teams. Tom Landry invented the coaching position called Quality Control. It was basically his job to scout the opponents and report on tendencies, roster changes, injuries, etc.
For 20 consecutive seasons the Dallas Cowboys had a winning record. They went to five Super Bowls and won two.
I'm not trying to justify Tom Landry's significance; I absolutely don't have to do that. I'm explaining why the Cowboys had a dry spell in the 80's when it came to drafting.
Twenty consecutive winning seasons means drafting in the lowest quarter of each round for 20 years.
Five SB's means that 5 of 20 or 25% of the time the Cowboys had the last or next to last pick in each round of the draft.
It's true that Landry is dead as you put it. However, he is remembered but not remembered enough by those that would try to imitate his achievements. They look at the results without paying attention to his methods.
I know one coach in this league that didn't. Bill Belicek was a great admirer of Tom Landry to the point where he incorporates a lot of Landry's philosophy and methods. It seems to have worked out well for him.