This happened to me as well. But the dupe would only use the animation for generating power on the manual generators. They would use the proper animation for everything else.
Dupilcants continue to go through the animation of working for a second or two after they've finished the job. For example they keep digging or building after the dig or build is done.
When a ladder is deconstructed when a duplicant is using it, the ladder will be destroyed but the duplicant will hang onto thin air and be unable to move. Even if another ladder is within reach they will not use it. Will try to grab a screenshot of it the next time it happens.