Interesting idea. Well done and good luck with it.

IMHO, the use case for async audio notes is not entertainment "podcast". People listen in a passive and linear way.

But the use case is team planning and note taking for on-the-go and hybrid WFH teams.

Add some ability to "call-in", listen and add comments and you've got something like an audio Kanban board.

Also add voice2text to dump a threaded transcript.