Part of the issue is they are utilizing Ceci notably as a shut down D man, you can see it in the defensive zone starts and PK time, which does explain a bit of the numbers.
But truthfully, that was not his game coming into the NHL. Generally a capable defender, but a shut down D at the NHL level? His game was offense. His game seemed to pick up last year when he was used in a more offensive role late in the season. Now he is back to the same place of being asked to be a shutdown guy. He's not that, and perhaps we are at the point we can say he never will be that.
But with EK in front of him, there is little likelihood he can play a different role. Brass obviously likes the skill, and thinks he can do it (at least better than the other options), but at this point I'm not sure I see it.
As such I expect him to remain a whipping post for sometime.