

One thing not mentioned, BTRFS supports transparent compression which hypothetically can increase the longevity of SSD media by reducing the amount of writes to the drive.
I say hypothetically because further information on use case (potential write amplification from CoW) could nullify those gains — but frankly, SSD write longevity has improved so much that it is not a huge issue at this point.
There is also last.fm. I would have suggested libre.fm but they are no longer open to registrations it seems
This would replace the “algorithmic” component of spotify, I would still suggest some other options (sharing stuff in your social circle, seeing who opens for your favourite groups etc.)