We have quite a few of these and the 13" Pros. I'll have to ask around. I would be curious to know if the poster uses any optical prosthesis and the latitude t

We have quite a few of these and the 13" Pros. I'll have to ask around. I would be curious to know if the poster uses any optical prosthesis and the latitude they're in. February in the north would mean longer hours in the dark or with artificial lighting. It also sounds like they may have just grown accustomed to the 2013 display over an 8 year period and haven't readjusted. I used a 2013 for several years, and it is lower resolution, muted, and dimmer than the M1. The pixels were almost visible. I might even suggest that because of the significant improvements to battery life and usability that they may just be tiring their eyes the natural way- by being able to use it more comfortably for longer stretches, to the point of RSI. As someone else suggested, the improved panel and color reproduction may also be confusing their focus and causing them to attempt to peer beyond the image, similar to the strain caused by Hulu-style DOF blurring to change the focus within a shot or misapplied artistic blur in VR like in Avatar. That was the case the first time I moved to a HiDPI 10-bit display- my eyes couldn't tell where the panel physically was and tried to navigate depth based on shading information alone.