Probably. E-ink drivers ("waveforms" is, I believe, the term of art) frequently target refreshes only at the portion of the display that has updated, using rectangles or other more-specific geometries to limit that area.

For text updates, where there's literally a cursor which moves at typing speeds, update frequency is quite low. Where you're updating or paging through documents, paginated navigation (where the whole screen refreshes at once, then remains unchanged for several seconds to minutes or longer) is quite efficient.