Interesting. Once again, I don't have a Kindle so I can't verify any of this. I do have a PocketBook Versa with stock firmware and a M5Stack Paper S3 running Crosspoint Reader, but hardly use either as I prefer reading on LCD or OLED tablets. The only formats I care about are DRM-free ePub and PDF.

Totally fair. I don't read much on Kindles either (mostly on my OLED phone). There's just a lot of dis/misinformation around these deprecations that I feel should be corrected. I worked on Kindles earlier in my career and still have a soft spot in my heart for them.