Probably. The offense and defense are not completely independent. But does anyone have stats for avg number of possessions by both our offense and defense? A slower offense will generally give the defense more rest, but that may evaporate if the offense is unable to sustain drives.
Immediate takes: Losing Wallace killed offensive production. Yes, Hubbard still got yards, but they were a lot harder to come by.
Offense was clearly down across the league, in terms of established star players. There was some damn good offensive talent that left the league last year & is playing in the NFL now, & the guys that replaced them just weren't as good.