I'm not sure I agree with the assertion that podcasts are a bad way to engage with ideas in the way that books allow you to. Of course many podcasts don't do this or even proclaim to, but my experience has been that certain interviewers/podcasters are really good at laying out ideas or worldviews that you can then evaluate yourself.

The one downside is that they generally take more time to go through and it's hard to know beforehand whether what you are going to listen to is worthwhile