Side note -
I literally have the reader pictured in the thumbnail. It is a Kindle keyboard from 10+ years ago at this point. It still works fine. At one point the original battery went to shit, and it cost very little to get an aftermarket replacement and install it myself.
I keep it offline and read 100% sideloaded .epub books from various sources. The lockscreen ads don't even try to display anymore.
Sure it isn't backlit or waterproof but it still functions flawlessly as a generic reader. Old tech like this is awesome. Why not get a decade of use (or more) out of something that still works?