I listened to this last night and found it worthwhile. I learned a few things I hadn't known before: he wrote parts of Dune in Haiku and other poetical forms, for the pacing those forms imposed, then expanded those parts into prose [1]. The magazine editor John Campbell turned down Dune Messiah because he (the editor) disliked (Herbert thought) the fact that the story explored the downsides to prognostication [2]. Herbert and the interviewer also discussed Joseph Campbell's ideas on cycles of stories.
[1] at 1:19:17 https://youtu.be/A-mLVVJkH7I?si=lMcNQJCB0dEYalIH&t=4757
[2] at 53:27 https://youtu.be/A-mLVVJkH7I?si=_Iz5-Dm9qcrHXd_H&t=3207