I agree with most of what you said except making another blanket statement that teams should be passing teams. If a team has the O-line the Cowboys have and a back like Elliott and can use up a lot of clock with that running game and keep the other team's offense off the field and still win games, that is a smart approach. That also helps keep the Cowboys defense better rested which is better at the end of the game.
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I think the NFL goes in cycles, for example we have seen the pendulum swing from AFC as power conference to now NFC, mostly because NFC teams were picking higher in the draft and coaching changes, etc.
same with offensive styles, they changed the rules to create more passing to have more scoring to attract more fans, teams learned that a 3-4 defense is more effective in pass rushing and its easier to find 3-4 OLBs than DEs and 4-3 defenses went towards, lighter faster DL and LBs for better pass rush and LBs that could run with TEs and WRs...now the pendelum is swinging back IMO, like you said.... the Defensive fronts are a little smaller and lighter and more susceptible to run game, so teams like dallas that started to build a bigger offensive line and heavy running are seeing success and we are seeing more teams go to that. for a few years the value of RBs were low, but now we are seeing RBs be valued and drafted higher in the draft.
it will probably continue to swing this way for a while and defenses will respond, change scheme and then it will swing back again.