It starts up front. You have players who don’t hold their gaps and keep the second level defenders clean. Aside from Jones, the other DT’s struggle with this. As much as Walker has flashed at times he’s shown some bad reps in run defense.
On the second level you have defenders who miss tackles - or who can’t get off block namely Bernard but also Williams, Milano, Poyer, Johnson and the CB’s all have fallen victim to this as well.
I don’t think they have the true run stuffer they need and it’s seems like it’s a philosophical thing because they value pass rush over run stuffing I want to see them sign Kaleb Saunders and rotate him with Jones