Right now, both Apple AND Spotify have an anti-competitive advantage due to the app store (with Apple Music getting a massive advantage, and Spotify getting a better deal than new competition entering the market).
Although a lot of streaming payment rates are set upstream of streaming services.
And all fees can be avoided by not taking payment via the App Store. A streaming service can even accept payment in the Safari browser in iOS via Apple Pay, and it would not cost them anything.
99% of musicians being paid small amounts has only to do with the population at large liking a very, very small percentage of music much more than the vast majority of music.
That was the crux of the case. Spotify was accepting payment through their web site in addition to taking payment via the App Store. And because they were processing their own payments, they could offer the same subscriptions for a lower price than on the App Store.
The issue was that Apple was not allowing them to inform App Store users that they could pay through a browser.
"Artists don't get paid fairly" is a tale that existed long before Spotify existed.
On the publisher/songwriter side, streams are not "public performances" under the Copyright Act (in the US), so royalties are not handled by the court-sanctioned monopolies that have been in place since the early 20th century (ASCAP, BMI).
And the industry has been fighting tooth and nail to make streaming services use performance licenses, not mechanical licenses. Here's a very good (long) overview https://www.theverge.com/2018/3/14/17117160/spotify-mechanic...
It's 10 years old at this point, but Sony's leaked contract with Spotify basically outlines that there's no such thing as a 'per stream' rate. Roughly, all the money available was split between the labels (with most favored nation clauses to get them even more money) https://www.theverge.com/2015/5/19/8621581/sony-music-spotif...
Also:
> Contrary to what you might have heard, Spotify does not pay artist royalties according to a per-play or per-stream rate; the royalty payments that artists receive might vary according to differences in how their music is streamed or the agreements they have with labels or distributors.
> In many cases, royalty payments happen once a month, but exactly when and how much artists and songwriters get paid depends on their agreements with their record label or distributor