Here’s a link for a little more background.

https://www.musicbusinessworldwide.com/deezer-strikes-long-term-partnership-with-speaker-maker-sonos-to-power-sonos-radio-globally/

While this deal could be, and most likely,  purely about marketing and/or cost savings for Sonos and Deezer, I find the timing of this deal and the rumored release of the Era speakers to be rather interesting. The Era 300 can be used for atmos music only when not in used as surrounds, yet the only atmos music content currently available is through Amazon music.  I’m wondering if this deal will also include atmos music content through Sonos radio.  Again, probably not, since there is nothing stated about that, nor does Deezer offer any atmos audio content right now.

wonder if they can outrank Spotify. 

probably not but for my use case as a secondary steaming service it works for me I don’t need two full fledged streaming services. Apple music is my primary service I use Sonos Radio HD as A complementary service    

interesting intel. We use Apple Music and Spotify. If Spotify goes the way of Netflix and stops family sharing, then Deezer will be its replacement. I used the free trial and really liked some of its features, but cannot justify 3 sound streaming accounts atm 

"Sonos and Deezer Join Forces for Radio Streaming Starting April 2023."

interesting