Now I understand what's behind the rush to video in podcasting... ad revenue. That's it. Just ad revenue.
Google wants you to do it because they couldn't earn money out of Google Podcasts, but they *can* shove ads in front of your listeners/viewers if they use YouTube.
And Spotify wants you to do it because they can sell video advertising more easily and earn more money doing it.
Forget what audiences want. This isn't about them.