Radio dominated the first half of the 20th century but the advent of affordable TV sets in the 1950s seemed to spell doom for the format. Yet, radio endured. Radio was able to create a distinct image for itself, separate from TV. I have own theories as to why (cars, transistor radios and the music industry) but nothing conclusive.
To be fair, I bet there’s a large market of people too cheap for a Spotify subscription but also too lazy to load music on their phone, who just want some sort of distraction while driving. After all, cars have had alternate ways to play music for decades now (8 tracks, cassettes, CDs, MP3 players via Aux).