Obviously I am not well-versed in all the legal requirements and many other commercial aspects, but to me 9000 is quite insane and surely can be optimized away.
And apparently Spotify agrees.
Because it's like a cliché example of an engineer with the view that some relatively successful real-world product—that they have no real insight into—is far easier to implement than the people who _are_ familiar with it have. You see this literally all the time, to the extent that it's become a meme, and it's hard to believe anybody would make that argument seriously.
Spotify might have too many engineers on-staff; reducing the service to "moving between 1MB to 20MB files from a CDN to user's devices" is a flatly uncurious approach to understanding what engineering challenges they might face or if that's really the case. It's a service that _adds_ 100k songs a day, for goodness sake.