What artist can get away without being on Spotify? There are really only two music streaming services that are important - Apple Music and Spotify. Just like t

What artist can get away without being on Spotify? There are really only two music streaming services that are important - Apple Music and Spotify. Just like there are only two app stores that are important - iOS and Android. Spotify has a much larger market share in streaming music than Apple has in smartphones in Europe. Can I side load my own music in my Spotify library like I can with Apple Music? (True you either have to either use your computer or the iOS GarageBand hack)