To many people, "radio" and "audio" are synonymous. In other words, if it does not have a picture, it is "radio".
Ask people from each of the rather standardized generation groups what that "thing" in their car that produces talk and music is called. A high percentage will say "radio" even if they never listen to AM or FM radio stations.
And, as traditional radio stations migrate... or try to migrate... to streams... and add podcasts and the like, we will have overlapping perspectives by actual users of all audio media as to the name or names they use for different services.