I found some great data and thought I should share it. Not much on fiction podcasts but Podnews helpfully collected links to data on audio and podcasting released by several big companies in the space:
-- Audacy's State of Audio guide presents case studies that suggest audio does better than social media, with data from Nielsen, Veritone, Claritas, and others.
https://audacyinc.com/state-of-audio/spring-2023/
-- Cumulus Media shares 7 New Findings About The Podcast Audience, from the Share of Ear study conducted by Edison Research.
https://www.westwoodone.com/blog/2023/05/01/the-cumulus-media-2023-audioscape-7-new-findings-about-the-podcast-audience/
-- iHeart Radio's State of Podcasting 2023, with data from Edison Research, Scarborough, and eMarketer.
https://podnews.net/uploads/iheart-state-of-podcasting-2023-via-podnews.pdf
I wish they would do more research on fiction podcasts. It's really difficult to find information on Fortune's Gate particular audience. But check out Podnews if you can!