The only way that anyone be worried about this slop replacing actual good human run radio is if they don't understand why people like radio & music in the first place.
And what hypothesis exactly is the experiment testing? Because it doesn't really seem like there is any new or interesting information learned from this.
I think you're talking about some Platonic ideal that just doesn't exist anymore.
Streaming services such as Spotify are increasingly filled with AI-generated songs and the average consumer doesn't seem to mind because we're not listening intently in the first place: it's just a background track we're not really paying attention to. I'm pretty sure that radio execs are looking at that and are taking notes.
For talk radio... if I had a penny every time someone on HN brought up that they're enjoying NotebookLM-generated slopcasts, I'd have a neat pile of coin. And I think it's the same story: most people listen to podcasts just to kill time. Soothing, zero-calorie LLM banter will do.