This is definitely possible, and this is definitely already happening. It may be hard for some people to even tell the difference between an AI generated script/audio vs 100% human curated.

what do you think about this idea?

It sounds like it would create podcasts that are either uninteresting, full of lies, or both.

What's the benefit you see of creating AI podcasts?

I sort of similarly used LLMs and speech synthesis tools to make a prototype that could generate short (<10min) podcasts in Mandarin on any topic I specified. Being interesting is less important in a language learning context, though it's notable that I haven't used the tool much and prefer listening to Mandarin audiobooks and real human podcasts, perhaps because they are more interesting.

Interesting, has that lanuage learning podcast been useful for you?

I made a prototype, I told 2 host to explain one book acutally it works really well after using in-context learning except for sounds.