Having never written a web-based desktop app in my life, this is all out of my butt. But at some point I think it reasonable that there are assumptions once the web app is working that don't cleanly port to Electron or summat, and no one cared to check or cared to fix it.
I’d love to use and support a music streaming service that allows me to incorporate my own files in a good way, but there doesn’t seem to be any great solution. I’m close to just migrating to a file-based approach and just keeping a big local library of mp3s/flacs (and Spotify as a fallback for stuff I don’t own yet or want to check out temporarily).
Apple needs to apply the Safari treatment to Apple Music and create a dedicated team that regularly releases updates detached from OS updates. This team needs to have a strong UX lead associated.
I agree with your reaction of dumb UI omissions. Spotify isn't perfect by any means, but they are doing a better job at looking at how people expect the app to work and responding to those needs with features.
For years after iTunes launched, you could be listening to Internet radio (REAL Internet radio, not Apple's BS "radio"), and there'd be artist and song metadata displayed in iTunes. But could you click on that and say "buy song from iTunes?" NO. I mean... WTF, I wanted to spend money on iTunes but Apple didn't allow that.
To my knowledge that was NEVER fixed. Incredible.
There was one year I upgraded my phone's iOS at work (probably 2016 or 2017), when heading home that night, the Music app no longer loads but a blank screen, even I have all the iTunes music on device locally.
Later I found that first load of that upgraded Music app has an Apple Music pop up for "free trial", that requires data connection. Before you dismiss that offer, you cannot even use the Music app.
Real happy with Amazon Music Unlimited, its a much better service in almost every way.
The UX is slow. It takes 5 seconds to add a song to my library now. Half the time images don't load - so I have a bunch of black squares with words underneath. Sometimes music just doesn't play. 5G/4G handoffs confuse it, forcing me to force quit and restart. The shuffle/repeat options are buried in a weird location. Should be right next to the play button. These are all relatively new problems (the last 6 months or so.)
I don't mind paying for software. But I'm not going to pay for half-baked efforts like Apple Music is quickly becoming, especially if the price keeps increasing.