In the most recent updates, Spotify has very slyly managed to remove its function for users to be able to cast audio to Google Assistant Smart speakers and smart displays, using a Spotify free account. This feature is now going to show up only for users that have a premium account. Thereby anyone who might make an attempt to do so will see a pop up that reads as “Premium only”.
There’s no assurance if this change has been applied to only Google assistant devices or in an overall manner. The HiFi feature that was announced recently, will consist of this feature, if it has actually been limited to premium users only. Otherwise, a premium account of $9.99/month or $14.99/month Family account will be needed to access the feature.
If a user links their Spotify free account with the Google Home app, the user might be able to access specific playlists or podcasts, going beyond the limitations of the audio cast.