Natural Limits of Google Duplex (and Other Concierges)

Thinking about services that will make a call on your behalf, such as Google Duplex, I’m wondering what are the practical limits. Two scenarios come to mind today.
The first was to pay for duties on an incoming package. This required only the tracking number and my credit card details. Providing that information along with the instructions would have taken less than a minute. However, the total time, including dialing, tool about 8 minutes. An easy 7 minute savings — one interaction, bam, done.
The second was to inquire about fees for a reward ticket with an airline. Hmm… I would have to explain to the concierge what I wanted the answer to, provide my membership number and PIN, the dates and location of travel. That might take 2–3 minutes and there might have been questions that they’d require my input for.
We’re thinking that AI assistants are going to send us to sipping cocktails on hammocks but the reality is that talking to humans isn’t likely to go away. At least not in the next 10 years.