I used to be able to actually buy MP3s from Amazon US. I actually have bought and downloaded a few albums this way.

Then they launched Amazon Music (or whatever its name is) in my country, which only provides app-based access to music, and also took away my ability to buy MP3s from the US website and neglected to add it to my country's version of Amazon.

I tried to follow those convoluted instructions to no avail. Did it not like my Linux box? Who knows. But a company that made its fortunes making buying convenient should know better.