Okay I have about 900 Kindle books that I've paid for. I've never dared try stripping the DRM off them in case Amazon somehow finds out and blocks my account, losing me the rest of them. But since Amazon's planning on deprecating my Kindle in May now I guess I have nothing to lose. What would everyone suggest? And can anyone recommend a good e ink reader to replace the Kindle that can read files from any source?
@afewbugs Calibre + DeDRM + instructions found online worked for me^w um this person I overheard at the bus stop (with zero retaliation from Amazon: how would they know?)

@considermycat @afewbugs I didn't try this method, but recently bought a book and only got a .acsm file. This first method: https://ratfactor.com/b/drm-sucks was the only thing that worked for me.

And ofc, Annas-archive (long live)

Removing DRM from e-books - ratfactor

@douginamug @afewbugs Yep, you need ADE to open the .acsm file, then Calibre + DeDRM to access the .epub and transfer to your Kindle. (For Linux, installing Windows ADE under Wine also works.) And if stronger .epub encryption becomes the norm (it's apparently being rolled out), I can imagine "buy a legit copy [so the author gets paid] then download off AA" may be my next recourse