Genuine question, why jailbreak an ereader? Is it to install another OS?
Ereader
Lemmy.world Ereader community
As it is an Amazon device, someone might simply want to de-Amazon their Kindle. Perhaps because of the megacorporation that Amazon has become, or just to boycott USA.
The interface on Kindles isn't exactly the best out there. For one, it's very focused on selling you new books, while reading those books was almost a second thought for the designers. The settings to adjust the reading experience is limited. One font size might be too small, but the next bigger is too big. Margins and line spacing have very limited settings. Also, Kindles doesn't support EPUB, which is ridiculous considering it is the most common e-book file format - we are talking about an e-book reader device here.
You can install Linux if you want to, but it probably isn't very useful. There are also games and some other apps. You can also repurpose the device, if you don't want to use it for reading. For example, if you are using Home Assistant, you could turn your Kindle into an information display or control panel.
thanks for the response. that makes a lot of sense.