As a sustaining member of two NPR stations in the Boston area, I believe very strongly in the value of radio. For me, public radio is such an important aspect of creating a healthy, vibrant, informed community. Radio is freely available to everyone, it requires no expensive hardware, no software, very little skill/learning curve, it's broadcast out to anybody who can pick up a signal with any thing that can receive it... from a $1 (or less) hand radio to a $2000 smartphone to a $5000 computer.
Now, someone might say, "But podcasts carry all of your favorite shows!" And I think that's true, and I primarily consume most of my favorite shows via podcast or streaming these days... Heck, I even listne to my two NPR stations via their streaming channels on my computer more so than via the radio in my car. But, those streaming channels and their podcast networks would not exist without that original investment in radio. While for-profit, ad-driven podcasting networks started around ~2010 (with Earwolf probably being the first major one), the industry wouldn't exist without radio, and specifically, the consortium of stations that make up American National Public Radio.
Commercial radio described in the OP has existed because advertising on commercial radio has, historically, been a lot more effective than advertising on the internet. This is changing, but advertising on commercial radio used to be a very effective method of getting people to buy something or do something. The internet introduced this massive race to the bottom on advertising so we think of it as an ineffective method of social engineering, but in the right format, it's not. This is pretty evident with podcasting. Companies like Earwolf and Gimlet have sold for many millions of dollars (Earwold $50m about 5 years ago, Gimlet $200m about 2 months ago), because people have a special connection to engaging audio and advertising... even with the "skip" controls.