comments:
compubomb posted on r/tools5d
I think that is a mistake, depends on what is on the other side. That might be a lag bolt. It's hard to tell the diameter of the screw but if it's a lag, it went deep into a joist and the other side of the head is keeping something down tightly. Probably better to just cut it with a cutoff tool, or a small wireless Dremel with a fiberglass cloth on the other side. https://a.co/d/09x0nT9h they're not expensive. Then just a patch of drywall putty. Edit: just realized that is the other side of th drywall, do what everyone else said, vice grip plyers and spin most of it out, hope you find it.