If you ever spot Spam (either in the forums, or received via forum direct message) please use the Report button at the bottom of each post to make sure a Moderator can handle it quickly. Thanks for your help in keeping things running smoothly!
Regrettably Spotify have not set it up so that Siri can be used on HomePods. Apple has made it now so that this could be done and indeed Spotify have enabled it on iPhone and watch. We live in hope but a thread on the Spotify community with over 1800 votes is attracting no response from Spotify.