What's the navidrome pitch?

You stream the music you own, it uses the subsonic protocol/API, and so is compatible with countless clients, letting your enjoy your lossless music on fancy hardware at home or cached on your mobile device when on the go.

Better Plex than plex for music built by people who know what they're doing that uses a common API among different servers and clients, including ones that glue to Sonos, etc.