Kobo has the same thing. Buy books on Kobo and they are on your device. But they also support ePub natively and ADE DRM natively so there's more options of where to source books before conversion.
Kindles have literally always behaved like that, from the beginning.
The very newest generation of Kindle changed the storage protocol from traditional mass storage (which was compatible with everything) to MTP, which is mildly annoying for Mac users, but it is still intended to just show up as a flash drive.
I agree on the freedom for geeks, but let's not fool ourselves into thinking non IT experts want to deal with files.