Apple Music, and particularly iTunes Match, are the opposite of "just works". I wanted to switch back from Spotify, but I found that Match had made a complete mess of my library. Half of my album art gone. Albums were striped with some tracks that were replaced with the iTunes store versions, and some left as my uploaded MP3 V0 versions (most obvious because, even with Sound Check on, the volume levels between each track differ greatly post-iTunes Match).

I've been able to look past a lot of the decline in Apple's software quality, but the data corruption problems springing up (Catalina Mail, iOS 13 Photos incidents also come to mind) are a bridge too far. The primary reason I avoid turning on a new Apple cloud service is that it's likely it'll do something highly undesirable to my data.