This is mainly a CRT refresh + flash + motion effect, not just a camera rolling-shutter issue.

A CRT doesn’t show the whole image at once: an electron beam scans the screen line by line from top to bottom. If your exposure was relatively long while you were rotating, different screen lines were recorded at slightly different camera angles, so each successive line appears shifted sideways. That creates the skewed/slanted look.

The rest of the scene looks more normal because it was likely lit mostly by the flash. A flash is very brief, so it effectively freezes the monitor frame, wall, and other non-emitting objects at one moment. But the CRT emits its own light continuously during the whole exposure, so its image keeps being recorded as the beam scans downward while you continue turning.

That’s why the distortion is mostly inside the screen area: the CRT content is time-varying light, while the surroundings were largely frozen by the flash.