Podcasting is much, much better than radio ever was.
Radio never had anything like Lex Fridman, Omega Tau, The Internet History Podcast, Gradient Dissent, or Econtalk. Where people with real expertise interview people with real expertise. In Econtalk's case you have interviews with a number of winners of the Economics sort of Nobel.
There was never anything on any radio that was like that. There couldn't be. So much of this kind of thing is too niche for almost all radio.
It's estimated that there are ~500K active podcasts ( https://www.thepodcasthost.com/listening/podcast-industry-st... )
Podcasting wasn't like radio when it started in the 2000s and it's very different now.
Sure, there hasn't been another serial, but instead there is so much great stuff out there.