At an ad-industry conference in New York this month, one of the key architects of Spotify's podcasting strategy outlined what she saw as the biggest challenge facing platforms: how to moderate content.

Chief Content and Advertising Business Officer Dawn Ostroff, the television veteran who had helped bring U.S. podcaster Joe Rogan and other top talent to Spotify, had been asked about the backlash to COVID-19 misinformation spread on his podcast as Neil Young and other artists withdrew their music in protest. She said companies faced a "dilemma of moderation versus censorship" and that there was "no silver bullet."

Content moderation has been a thorny challenge for online platforms. While social media companies like Meta's Facebook and Twitter have faced pressure to be more transparent over moderation and ramp up investment in human and artificial-intelligence review systems, podcasting has often flown under the radar.