Nothing you've quoted is wrong per se, but it's also not the full story.
Amazon removed the ability to download files from them to your computer. And they will soon be removing the ability to download files from them directly to older kindle devices. You can still download a MOBI or EPUB from anywhere else online (though I think some older kindles don't support EPUB) and transfer it via USB, and will still be able to after they EOL those older devices.