I believe the human voice-actors are justified within this context. No comment on anything else but how does a “free market” come into play with this? It seems consumers should be able to choose between an AI narrated and human narrated audio book - given equal access to both. I personally am not a big fan of AI but playing devil’s advocate to a degree it seems AI narrated books may be useful for translating works in…
If humans want human narrated books, they'll get access to both. Human narration will only disappear if people aren't willing to pay for it. I'm pretty sure that ultimately AI narration will be so much better that human reading will be a niche thing, but I view that as a positive overall. More books get read with high quality narration, and consumers don't have to cover the cost of a human narrator.
Obviously unfortunate for the human narrators, but that's why we should be pushing for UBI - AI and robots are going to eliminate a lot of professions, and I think it's wrong to keep jobs around for no other reason than to keep people employed, especially when doing so ultimately leads consumer costs to be higher. You see this in lots of places now - a big one is the teamsters using their union power to keep automation out of our ports. Literally everyone in the US could benefit from goods moving more quickly, efficiently and cheaply through our transportation infrastructure, but instead everyone has to pay a bit more so humans can keep unnecessary jobs.