This is plainly not true. O'Reilly sells their books DRM-free to a very technical audience. In the US, at least, music that is purchased() today is sold without

This is plainly not true. O'Reilly sells their books DRM-free to a very technical audience. In the US, at least, music that is purchased() today is sold without DRM. DRM is user hostile and not required to make money. () purchased does not include Spotify, Apple Music, etc. of course, because those are specifically renting the music.