I’m fairly certain a big reason behind Amazon doing this is that older kindles make it trivial to pirate kindle unlimited books. Check out 20, move them off the reader into calibre, decrypt, return the books, get 20 more, etc.

(And before anyone says that the drm removal doesn’t work on kindle unlimited books, that check is two lines of python to fix.)

That’s stupid. Nothing stops you from just installing regular Ubuntu if you love snaps so much.