Spotify at least does allow you to add local files on a computer, and they even sync tracks to your phone when they are on an offline playlist when the devices are on the same network. I’ve done that myself to get some otherwise unavailable songs into my catalogue, and am thinking of starting the move to owning all my music that way
Funnily enough, the CEO of PostNord Denmark also earns ~700k, but DKK, so that is around 1.5 time that, but for running the part of the company with more losses
Source (p. 23)