Hive was used because the guy who built is a huge Hive enthusiast, built it out, and proved its usefulness. And it has been proven to be quite useful. If someone built a better solution on nostr that proved to be as reliable, I don’t see any reason for it not to work on both nostr and Hive. The podping api could simply notify both networks of the updated podcasts. One thing about the PC2.0 community is they’re very pragmatic but busy, so the builders decide the direction of things much more than the idea makers.