We can't narrow this down to just one issue for the Seahawks. They're struggling to run the ball, and they can't keep Russell Wilson upright. The common thread between those two? The offensive line.
Starting with the ground game, they finished 25th in Adjusted Rushing NEP per play, a hop, skip, and a jump from last year's sixth-place finish. Both Thomas Rawls and Alex Collins have a Success Rate below 30%, and the league average for running backs is just above 40%. No matter the matchup, they'll likely struggle to move the ball here.
Preventing Wilson from getting pressured in the pocket isn't a new issue. They were 24th in Sack NEP per drop back this year after finishing 25th last year. Again, generating a pass rush is the biggest shortcoming of their first-round opponents in the Lions, but this will be a struggle down the road should the Seahawks advance.