Apple Music has 3 things Spotify does not that make it a must-sub in my opinion.
The first one is catalogue. I have found some pretty obscure stuff on Apple Music that isn’t on Spotify.
Second is payouts. I know both are a pittance but Apple Pay’s artists double the pittance. Apple also still operates the iTunes Store so you can support your favourite artists with direct purchases outside the subscription really easily.
Third is the biggest: iTunes Match. Windows or Mac, Apple Music syncs my MP3 library to the cloud and integrates it directly into the library on my phone. Both Spotify and AM have some pretty big gaps in their collections so the ability to buy cheap CDs and rip them for cloud streaming is brilliant.