Just wondering out here, cause Im really torn between these two. With Spotify family and Apple One I use both alternately and in both Im missing some parts that the other one have.
for Apple Music I mostly lack good new songs suggestion algorithm, because it very often just plays me a song that I would never ever listen to - and that's based on "continue playing" from current playlist.
for Spotify I lack Losseless and Spatialise.
in terms of UI, both are somewhat not great
Apple Music is cumbersome and hard to navigate to song that is currently playing.
Spotify is just too much noise on the screen for me
For me, the dealbreaker with Apple Music is that they nuke your library a few months after you canceled your subscription. I tried it back in the day when it was new and used it happily for some time, but the difficulty of finding new tracks that I like drove me back to Spotify. I then wanted to give AM another try recently, only to find out that my old library was empty. I immediately canceled the AM trial after that…
Also I found that Spotify has a greater pool of niche stuff that I listen to.
The other reasons why I prefer Spotify have already been mentioned:
better discoverability of new music
better cross platform support (I use both Mac and Windows)