Wouldn't be impossible. I'm old enough to remember the original B+W game boy, and my B+W e-reader refreshes faster.

I've seen some very recent niche tech demoing fast-refresh e-ink screens but pretty much everything until now has required a noticeable flash to clear the entire screen on update. Which is fine for reading books but not for quick animating in an action game.

Most e-ink displays do not refresh faster than the original GameBoy which was 60fps.