His proposition may sound simple to him, but it really isn't. It becomes very hard to ensure you are being paid properly in his proposed scenario, I would personally expect it would create even more controversy, or extremely long payment records every month for artists. For instance say we have 500 paid users. Lets call them user1 through user500. Each user listens to the same number of songs a month as the value fol…
There are already a bunch of assumptions in the payment model, do you pay per track? (In which case, the artists could game it by sticking in 30 second intro tracks and things like that). Do you pay per minute? (In which case, artists can increase their revenue by putting in dead time in "bonus tracks").
It would be an interesting experiment for Spotify to calculate what the payouts would be given the proposed scheme, and compare the differences.
Anecdotally, the people I have met that work at Spotify are a lot more sympathetic to the indie artist and non-Top 40 music than the average person listening to Spotify. There is a reason they keep building ways to discover non-Top 40 music. I'm sure they are interested in making things better for these types of artists.