An alternative could be to use last.fm.
Many self hosted streaming servers or media players support scrobbling (sharing what song you listened to) to last.fm. You can then see your music history across different streaming platforms (including self hosted) and have tailored recommendations for new artists or albums on the last.fm website.
A few downsides are:
- Recommendations are not integrated into your music player.
- Not self hosted (there seem to be some alternative, but I don't think they will make recommendations), you depend on last.fm.