I have a dedicated music player with all my favorite music for offline listening (fiio x3 and also a pinephone with lollipop)
I also have a Jellyfin server and use finamp on my phone. It isn’t public so I have an always on WireGuard vpn.
For my stereo, I have a raspberry pi hooked up. It runs mpd and mounts the same music directory as Jellyfin using nfs.
The raspberry pi also has an nfc reader and I have nfc cards with printed artwork on them. Tapping them to the reader starts playing that album.