Ofcom’s Media Nations report is an excellent analysis of media consumption and trends, with a great section on radio and audio.
One of the opening paragraphs is a good overall analysis of the sector
Consumers continue to listen to radio and audio content on a wide range of devices. Although listening to live radio on a radio set has been in decline for the past few years, for adults overall it continues to account for much of their audio consumption. Conversely, consumption of digital audio services, including online live radio, music streaming services and podcasts, has grown over time, especially among adults aged 15-34 for whom live radio on a radio set now accounts for less than a quarter of listening.