Per Jimmy Kempski:
In a sense, this isn't surprising. Rex Ryan has always been known to make stopping the run with his defensive front his first priority, rather than rushing the passer. It's easier to do that with big bodies up front.
There also doesn't seem to be a correlation between good defenses and the weight of their front seven. For example, you have the New York Jets, Baltimore Ravens, and Kansas City Chiefs at the top of the list. Conversely, you have the San Francisco 49ers, St. Louis Rams, and the Seattle Seahawks at the bottom. What do you think?