Very interesting. With the speech to text APIs out there would be interesting to further expand to point in time queries of the articles. Similar to the https://podcastsearch.david-smith.org.

Facets would be a nice to have - such as:

Series, Category, Guest, Date

Extra credit:

Speaker diarization and be able to search by individual speakers! If multiple channel feeds were available for the podcasts this would be easier to do... Maybe a search engine for podcasts where you partner with the content creators and give them incentives to tag/provide better feeds?

edit formatting.