The speaker discussed podcasting 2.0, focusing on the concept of interoperability. They argued that podcasting 2.0, an open source and decentralized system, could save the open internet. They highlighted the importance of content creators having control over their content and the drawbacks of closed platforms. The speaker also explained the podcasting 2.0 specification, which includes features such as alternate enclosures, boostograms, chapters, transcripts, and more. They showcased Castopod, an open source podcast hosting solution that is podcasting 2.0 compatible and emphasized the need for user support and adoption for the success of podcasting 2.0.