Is this fully open-source, or just the clients? eg. can you use them with out any interaction with the pocket cast server, and subscribe to podcasts using open/other feeds?
I'm with you that allowing the clients to connect to a different sync server (gpodder, etc) would be a great feature. Though, again, I don't see that happening because it would cut into their subscription service.
Though I suppose if there is enough benefit to the free product (I'm not that familiar with it) - and confidence it will remain free - that might be a draw.
Perhaps there is also potential for it to be forked for a genuinely open service - I'm just a bit sceptical about "open source" that doesn't keep the implied convention to be fully independent, but perhaps that's unfair or unrealistic here.