How dare you question the ultimate superiority of RSS over Nostr?
Yeah, it will need a new NIP just for podcasts. I would not do it for "any audio file" but specifically for the needs of podcast apps.
nostr:nprofile1qqsrhuxx8l9ex335q7he0f09aej04zpazpl0ne2cgukyawd24mayt8gprfmhxue69uhkcmmrdd3x77pwve5kzar2v9nzucm0d5hszxnhwden5te0wpuhyctdd9jzuenfv96x5ctx9e3k7mf0qydhwumn8ghj7un9d3shjtnhv4ehgetjde38gcewvdhk6tc4rdlnm's NIP is a good start, but needs to update the comments to NIP-22.
Discussion
:)
I know this is a joke, but RSS != Podcast.
Trying to make them fit together is a mistake.