If the market believed there was growth potential, their annual returns would not be trailing SP500 by 3%+ per year.
Amazon’s market cap grew by much more than the SP500, because the market (correctly) anticipated Amazon being able to earn profits.
Spotify’s ability to earn decent profits is not a given, and in my opinion, their whole business is currently being a negotiating chip between the 3 businesses that own music copyrights (Warner/Universal/Sony) and Apple/Amazon/Alphabet.
Amazon did the same for a long time. It’s a fine strategy if your investors don’t need the immediate returns.