In the iOS Google Home app, I added the voice assistant as a favorite. When use voice commands to play music on the Play 5(gen 2) or the Playbar(gen 1) the assistant just shows a google search. Both the Playbar and Play 5 devices show up in the Google Home app after linking my Sonos account. I added Apple Music as the default music service to both Google Home and Sonos as well.
When I use Youtube Music as the default music provider it works.