The apps are terrible in terms of usability, performance, and reliability. I couldn't believe Apple dropped the ball on so hard on this, but then I remembered iTunes and started believing again.
Most of my problem is basic necessities. For instance, it's impossible to remove a playing song from its current playlist on competing apps. That's such a common, basic scenario that Spotify can perform easily.
Youtube Music has horrible sound quality, no need to say it doesn't provide a lossless option. Apple Music is on par with Spotify in sound quality but that's pretty much where Apple's competitiveness ends. I had to struggle with Apple Music even with the simplest things.
My Apple Music summary: https://bsky.app/profile/ssg.dev/post/3m2mvmybjr225
My Youtube Music summary: https://bsky.app/profile/ssg.dev/post/3m5ms6fxsrs27