Former Google Play Music users who recently had to migrate to YouTube Music were previously not allowed to cast songs uploaded to the service without having a Premium account.
This restriction, which did not exist on Google Play Music, is now lifted on YouTube Music. Service users can thus enjoy their own songs on speakers and connected TVs without having to go to the cash register.
In addition, YouTube Music now works much better with Google Assistant. The service now allows you to start reading your personal playlists by directly requesting Google’s voice assistant.
Source: The Verge