Part of that is a lack of a focus on podcasting. Serial drove a lot of interest, and that momentum faded with no obvious replacement. Podcasts were something folks made time for on their commutes and during their workouts. When folks started working from home en masse, they had less and less reason to listen.
Listenership fell for shows that have remained consistent. Some of my biggest customers have half or less than the number of listens they were pulling per week in 2019. And that's without changing cadence.