When I consider, for example,
Lineage v20 for →
A9
https://drive.google.com/drive/folde...ENkBH1ATPBlymA
From :
https://www.reddit.com/r/eink/commen...or_hisense_a9/
.. so, according to the post, it doesn't really smell like optimization. In addition, the only setting for E-INK is the "E-INK center", which does not have half the setting options as ONYX, for example. Those comments about the problem and inaccuracies of the LED backlighting do not look very convincing either.
However, I've never tried A9 devices with Lineage, so I'm not condemning it, and I was more referring to devices like BOOX ONYX type Leaf/Page/Nova etc..
If someone uses E-INK screens (10 inches and similar) as a replacement for the LCD monitor from LineageOS, it can bring more freedom and control. Of course, if you don't go through the entire "source code" then you can't be sure what the device "sent" and "receving" if you understand me.
PS: It might be interesting to have most of the E-INK devices
I understand the installation of another OS in your case, but I think it's an expensive hobby
But some users simply need to constantly assemble something and install something, some of the listed items are then used only as an excuse "why .."