I gave up, bought a kobo libra2 that never saw an internet connection (you can find updated firmware online to download) and now just borrow epubs in the soulseek library.
I also just brought the cheapest oldest b&w model kobo reader still on sale and put epubs on it. Haven’t even updated the OS. Just works. Sweet.
I hope the kobo store has rigorous screening of their books, unlike Amazon: https://news.ycombinator.com/item?id=47386280
These days it's hard to even get a proper book to read.