As others have said, do not twist the spudger. To release the display, you only need to create a gap of a few millimetres. Better to slide the spudger as directed to release the adhesive, bottom left and right.
Used heat from a hairdryer, gentle pulling to lift the glass at the position above the headphone jack one to 2 millimetres with the suction cup, then put my thumbnail in the gap and pulled up gently a bit more to fit the spudger, and mainly slid the spudger as indicated around the glass, bottom first, and then sides to within about a centimetre of the top at most, to release the display. I found very little prying is needed. Once a gap of about a millimetre or 2 is created, that is enough to release the display from the adhesive.