This still uses a classic electrophoresis panel, perhaps even one that is produced by E Ink. These work by moving solid particles (pigment) through a liquid. Which is inherently a physically slow process. At high refresh rates there will be significant amounts of ghosting.
To get past that, we would need a different panel technology, a type of reflective ("e-paper") panel that is not based on electrophoresis.
Years ago there were many such display types in development. One option is electrowetting displays. Liquavista was a company that had a screen where tiny oil droplets were switched between being either round and small or flat and large, using high voltage. The flat droplets would cover the background of a pixel and make it dark, while the small ones would "hide" in the corner of the pixel to make most of the background visible. This is pretty fast because the oil droplets are surrounded by air, which doesn't resist the movement of the oil, in contrast to moving solid pigment through a liquid.
Another option was to to have microscopic mechanical (MEMS) plates inside a pixel, which produce color by creating light interference. Qualcomm's Mirasol tried to do that. The wavelength of the reflected light depends on the gap between the plates.
The cool thing with interference e-paper is that you can theoretically make a color display which doesn't need RGB subpixels. Colors could be created by continuously adjusting the gap rather than doing binary switching between black (UV or IR) and either red, green or blue. Not having RGB subpixels greatly increases contrast on colored screens because it can reflect much more light. An issue is that shades of white and magenta can't be straightforwardly created with interference, because those are not monochromatic colors with a single wavelength. Anyway, Qualcomm closed Mirasol just as they tried to make these subpixel-free screens viable.
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