I dont know for how many years players have been reporting getting stuck in walls. What I know is that still isnt fixed. If you dont want to remove the fear effect on players from bosses, at least make player's characters stay in place and not start running into walls.
This happened today in Volenfel. We were fighting Quintus and he cast fear on me, with the result being me stuck in the wall.
It is a very common issue in Wayrest Sewers and Crypt of Hearts too.