Even if you don't subscribe to Groove Music yet, Microsoft is making it easier for you to check out the different features the app offers. As announced by Microsoft's community manager Ellen Kilbourne, non-subscribers can now check out more of Groove's premium features like the Radio tab.
From Ellen Kilbourne:
@ellenment The change makes it easier for you to see what the service is all about if you're considering becoming a subscriber.— Ellen Kilbourne (@ellenment) July 22, 2016
It's a minor change, and you still have to be a Music Pass subscriber to actually play anything from the Radio or Explore tabs. However, if you're considering a subscription, this should hopefully give you more of an idea of the service's merits before diving in headlong.