“Starting on February 26th, 2025, Amazon is removing a feature from its website allowing you to download purchased books to a computer and then copy them manually to a Kindle over USB.
“It’s a feature that a lot of Kindle users are probably not aware of, given books can be more easily sent to devices over Wi-Fi, but it’s especially useful for backing up purchases or converting them to other formats compatible with non-Kindle e-readers.”
Read more at The Verge