The cracks were starting to show in DA's defense. He was elite in the era of pocket passing QB's. In this new era of more mobile and scrambling QB's he'll struggle. We've seen it whenever we faced a nobody QB who would run when his first read wasn't open.
The good thing for him is McCarthy/Donald, Love, and Goff are not thought of being very mobile or great scramblers so maybe it's the right division to land in.