Your math assumes those people only have one track on Spotify. I currently have 25 tracks on Spotify. Without advertising or promotion of any kind, I earned about $12 this year. The big problems are:
I have no delusions about ever making a living off Spotify (or my extremely niche music in general), but the idea that a corporation should be able to monetize my work and not have to pay me anything for it is sort of distasteful
TemUmbridge