/diy/ - Do It Yourself

I'm not a /diy/ guy but a family member messed up and wants me to fix this situation
They're trying to replace a ceiling light fixture and they need to replace a bracket, but the screw in this picture got stuck which lead to it being stripped by a drill
I tried the rubberband trick and it still wouldn't so I tried turning it manually with some pliers, and it will turn clockwise but not anymore counterclockwise
How hard is it to remove and replace the electrical box? Or is there some other way to get out the screw? Thanks