@pho4cexa @Jo No need to go as far as eink - a nice and big TN LCD would do just fine ;)
Example: The TRS-80 model 100 from 1983. Main focus was word processing on the go with installable applications. Internal modem and 20 hour battery life on 4 AA batteries.
https://www.pcworld.com/article/146496/article.html
@polychrome @Jo from my brief searching it seems like the writer's favorite device before the Freewrite came along is the "Alphasmart Neo" from 2003 (pic)
i wish at least some modern-speed tech aimed for old, cheap and open instead of locked-down, high-res, and color
i've got a parts box full of old palm pilots that i hope to someday be skilled enough to scavenge the LCDs off of to re-purpose
that said, i like e-ink too, and modules aren't very expensive: https://www.waveshare.com/product/4.2inch-e-paper-module.htm