Very cool idea. Probably also needs an app to really gain traction (maybe just start with a webview and not a full native app?). I think lots of people are listening to podcasts on smartphones.
Agreed, I am also working on a react native app for iOS and Android. I decided to release it on the web first to avoid the extra cut Apple and Google will take and to iterate faster on a single platform, but as you mention, most people expect to have a native app for these B2C apps.