Music apps especially went downhill, spotify and tidal etc need to offer apis so we can integrate several sources in one app. They used to offer much more. I was able to import my library into spotify once (thoigh it could only hold 10k item back then). I want all my music in one place, not 4 apps

They don't offer APIs precisely so that you can't integrate several sources in one app.

I have Gonic (a subsonic server) on my home server and my client is a perl script. It basically allows me to search for an album, present a prompt for me to select the best match, and then builds up a playlist for the tracks to pass to MPV. That’s pretty much all I ever need. I would gladly dump the whole spotify client if they had an API to do the same (even if the queue is a long stream of data instead of tracks).