I'm not sure "per stream" is a useful metric, as artists don't see equal stream counts from each of these platforms due to huge difference in these platforms' reach. YouTube ranks low on this list, but I imagine they're the highest if sorted by total stream count. So while YouTube may pay low "per stream", they may still be the larger revenue source for some artists just due to the total plays they receive over other platforms. Not saying this in defense of YouTube or any other streaming platforms, just saying this in defense of math; I can't imagine that many artists on these platforms are receiving larger checks from Napster each month than they are from YouTube.

There's lots of other factors to consider, too. Each of these platforms have varying degrees of providing alternate revenue to artists, through ad subsidies, merch stores, concert ticket sales, etc. Also, how much the platform pays out per stream, and how much the artist receives per stream, aren't always going to be the same amount, as labels will generally take a cut of this revenue first.

This graph really doesn't tell a full story.