Spotify had a first mover advantage and is now using network effects of playlists and recommendation to keep their market share. If anything it's a testament to the power of Apple and Amazon that they were able to gain significant marketshare.

Trying to directly compete with Apple and Google in the mobile OS market would be like trying to compete with Boing/Airbus or TSMC/Samsung, in that the capital requirements are so astronomical without extreme forms of subsidies and protectionism.