Ngakoue is younger
This is the number-one-with-a-bullet difference. Nothing about the Everson Griffen and Yannick Ngakoue switch is more important than the age differential.
Griffen will be 33-years-old this December while Ngakoue turned 25 this spring. For many NFL players, that is an entire career’s worth of age variance.
The Vikings essentially pressed the reset button on their defensive line in terms of esteem. Griffen, had he remained in Minnesota, would have finished out his days in a less prolific fashion. It’s just what happens to aging players and especially those buried in the trenches.
Ngakoue murders that scenario. His teammate on the other side of the defensive line, Danielle Hunter, is also 25-years-old. Instead of the Vikings watching Hunter be the showstopper while Griffen mopped up the remainder of defensive boxscores, Ngakoue and Hunter join forces to collectively induce mayhem.
There is a feasible and potent possibility that the Hunter-Ngakoue doublet anchors the front of the defense for several years, which is the stuff only horror film scripts can bring to life.