Agree with @fireal99! Those sheet rock screws are sharp, aimed up and the tips are exposed near all those wires!!!! Any movement of those large gauge wires and they risk being pierced. This is a hazardous scenario. Those wires need to be protected up in the ceiling from those sharp points and, while not always required by code, where they drop down to the panel. Boxing this area in would have been a much safer solution all around. Also now those wires are sealed in/embeded into the joint compound and if you need to pull one or fish another, you could not. This is probably a code violation. Generally a bad solution...

Perhaps building a soffit box to encapsulate all those wires would make it look cleaner as well as give the wires some room to move and dissipate heat build up.

...mmm YIKES !

Dremel next to live wires, what could go wrong, but seriously I get the part to make it smaller and they sell plastic access covers with spring clips to hold them in place that could be fitted to cover the hole then you can dremel some space in corner edge of the cover for wires but I think doing permanent fix next to electrical panel and main wires might end up being bad idea especially if any screws that are longer than material pop up from the back into the wires and causing some electrical short, then gaps will be least of your worries. In the future if any new lines need to be added the whole thing will have to come apart to become what it looked before.

Box all that in with drywall.

So many things wrong with this

first time in my life I see somebody pre drilling drywall....