But why would you download a (probably illegal) rip that is poor quality, when the act of downloading and keeping the rip is probably illegal in itself (not exactly sure about that) from a platform that is notoriously unsuitable for music when you could just download high-quality release from a music tracker specially optimised for this use case?

I mean, if you are ok with doing something (probably) illegal, why not get the best experience out of it?

Open source command line clients for specific streaming services inherit the catalog issues, but FYI:

Pandora - https://github.com/PromyLOPh/pianobar

Spotify - https://github.com/plietar/librespot

You could also use Atraci which streams off YouTube:

https://github.com/Atraci/Atraci

I believe it downloads the whole video, then extract the sound. At least you're downloading only once, but one of the points of streaming music is not keeping the music on your disk at all.

Plus, it's pretty illegal if I'm not mistaken!

Plus, sound quality on youtube isn't very good

Thanks for mentioning it, I love that tool (even got this on my phone in a Debian subsystem). Still, it's not suitable as a replacement for Spotify: the discovery element is too useful :/