Currently, I have a Spotify and Google Music subscription. Along with the limited Amazon Music steaming that's free with prime.
I have to give Spotify credit, they are like the Facebook of music streaming. It's the most integrated service. Damn near every hardware/software is compatible. Whether it's a smart TV, home assistant device, game console, smartwatch, and etc. It's also the easiest to switch sound output to whatever device. Even Waze maps has Spotify integration which works very well. Their available music seems better than even Apple music in my experience. I also like the fact that you can pay yearly if you want.
Goggle Music is my second favorite. I'm fortunate enough to keep finding 3-6 month free trial deals on it. Haven't pay for Google Music for at least a year. I like the UI the best since it fits the overall Google style. It also does something Spotify doesn't do well, with is play local music files on mobile. You have to connect to the same network on as your computer then download local files with the mobile app. Google music just detects any local music on your internal or SD storage without the need to do that. Also, Google Music has their free upload service, that you can stream from anywhere.
Amazon Music service that comes with Prime gives you a pretty decent selection for being a limited service. The downside is, even the full paid service is limited in selection compared to Spotify, Apple Music, and Google Music. The upside to having Prime is they have a limited Movie streaming service too, which is not bad. I use the Music and Movie streaming that comes with Prime on occasion. I treat it more like a backup service.
Apple Music is great on iOS and MacOS. But the software is not that great on Android and PC. Also, the least integrated and compatible outside of the Apple bubble.