Commercially, I struggle to see how this fits in to the most natural application, a contact center.

For example, take Amazon Connect pricing:

There is an Amazon Connect service usage charge, based on end-customer call duration. At $0.018 per minute * 7 minutes = $0.126

There is an inbound call per minute charge for German DID numbers. At $0.0040 per minute * 7 minutes = $0.0280

If I were to bring retell into the loop, I'm changing my self-service per minute cost from .018 + .004 = .0184 per minute to .1184 per minute at the cheapest setting. And from that, I don't have a clear case for the impact on deflection, and because of that I don't have clear ROI.

This isn't saying that the product isn't great -- but at the current price I struggle to see how anyone at scale can use it without eating the double whammy of LLM + Retell costs.