The music labels - the copyright owners - are barely mentioned in this article at all, yet they are where all the money is going, incrementally, for every stream played.
They're the rentiers sucking it out of everyone else. Spotify does make a profit, but not a large one, because the costs of paying the copyright holders are so large. Yet the share of artist money from the copyright holders is tiny, so the big labels end up rich while artists end up screwed (especially smaller artists, as the article correctly points out) while the record labels end up on top.
It's really not Spotify sucking everyone dry here - it's the record labels, and it always has been.
(I have nothing to do with Spotify, I'm simply pointing out the vampire squid behind the mere octopus this article is blaming).