It's cyclical, the whole league slowly transitions to the flavor of the month defense (see also: Tampa 2) and currently the 3-4 is becoming more favored in a league that is very pass friendly.
This is also one of the reasons I personally think they need to look at the overtime rules again, every year they make more rules to hinder the defense in the name of competition or safety.
This is also one of the reasons I personally think they need to look at the overtime rules again, every year they make more rules to hinder the defense in the name of competition or safety.