I stay on Spotify because it has an open source client spotify-qt.

I use Firefox on BSD which doesn't have DRM support so the web versions of Apple Music and Deezer don't work properly. On Apple it only plays the first 30 seconds of each song and I forget what the problem was with Deezer.

Also a real app is way nicer than a web interface of course. And with libspotify I can even change songs that play on my mobile and control it through home assistant.

None of the others allow third party clients or open source. Sure it's a niche reason but this is the reason I'm on Spotify and not somewhere else. I've tried other platforms for a month but it was crap.

I only listen to big artists anyway that are well compensated.