IMO it's much more likely that we'll end up with the same visually overloaded GUIs, just running on a color, 60fps eInk display than having the whole industry return to static black and white.
It can't improve unless you change the underlying physics. Electrophoretic displays like E Ink's use particles in a solvent. They can't move fast because fast moving particles are not going to be stay in a stable position. Have a look at those displays from 2008 and compare it to 2020. The quality of the display has changed, contrast is better, but timing is still about half a second. Modes like A2 which is used by Dasung are just hacks that tradeoff speed for stability and perhaps even panel life / reliability.
The startups doing fast displays typically use a different underlying physics. But no one wants to invest the necessary billions in them so they keep dying out like Liquavista, Mirasol and many others.