A slow motion capture of CRT show's the issue https://www.reddit.com/r/crtgaming/comments/7w0v02/video_by_...

Almost laser pointer brightness at one point on the screen which you don't consciously see because the your eyes and the hold the image for a few milliseconds but do you really want to be looking at a extremely bright point of light all day. Higher refresh rates on CRTs lowered eye strain since that point could be effectively lower brightness, just refreshing twice as fast.

I honestly don't get eye strain on LCDs nearly as bad under any circumstance. 60hz LCD was a massive improvement over the 120hz CRTs.