I think the podcasts i listen to will not work, the moderators speak the ads themselves. Luckily it‘s easy to skip ahead 15 seconds at a time.
At least ads in podcasts cannot track me so i don‘t feel i have to block them for that reason alone.
The startup I worked at used it for contests, out of 100k downloads of a podcast, 1 of them would get a different starting or ending segment to give away something. So it was persistent to your user-login on the podcasting portal (which was a thing back then :-))
All that said, the best ads (from a listener experience POV) are the extremely short, to the point ads that are honestly too short to put the effort into skipping. Planet Money (and the NPR podcasts I listen to in general) does this well. I'm curious what their CPMs are relative to a typical ad.
The latter is unthinkable on commercial radio, where separating ads from 'content' is a skill unto itself.