Spotify’s enormous access to mood-based data is a pillar of its value to brands and advertisers.

Spotify pursues emotional surveillance for global profit: https://thebaffler.com/downstream/big-mood-machine-pelly.Don't let them harvest your emotional info! Instead, help better services powered by free, distributed software like libre.fm grow.
Inside Spotify’s emotional surveillance-driven quest for total ad domination. https://libranet.de/display/0b6b25a8-205d-0212-99eb-9f0720225523