It seems very limiting to me and I would of prefer if Sonos let you know in advance that your primary music source comes from Spotify and not from whatever you like to play from your phone.
Spotify to me is very limited and hard to search for songs, always throw more modern versions of the songs not the original and if a musician is not on Spotify you won't find the song you are looking for.
Youtube video is much preferred for me as I can find any songs that comes to my mind, plus the autoplay is way better than Spotify and remembers your preferred style of songs, Spotify autoplay is not smart this way and it just keeps throwing horrible songs.
So now I have to play music from my computer not from my phone.