You don't need to clone someone's voice for that; that's a scam common enough that one of my parents almost fell for it. Cloning someone's voice might tick up the likelihood of success by some amount, but would the investment in the research-and-infrastructure (spinning up the machines to clone the voice, researching the person you're planning on scamming to find their relatives' phone numbers, etc) be worthwhile when you can just dial every phone number in the tri-state area and just try it with a panicked-sounding young woman's voice?
Scarier still is the knowledge that today, I can spot a scam call immediately - but a future is coming where I'm the one who'll be likely to read off my credit card number to someone on the phone.
They just call at 3 am, cry and cry to make the voice difficult to recognize and then a friend/kidnapper/corrupt-police-officer ask for the money.
We will lose a lot though; the most prosperous societies really rely on high levels of interpersonal trust (which allows people to easily do things together, whether that's leaving their buggy outside when they go to buy a coffee or commercial relations). It would be a shame to see that get destroyed.
I get a call and there is a green checkmark saying "GPG VEIFIED" and then I know it's who I expect.
The countermeasures won't destroy trust - it's the fact that you can't just pick up the phone and work out if you're speaking to a real human. Or trust that posts on an internet forum are from real people, and not just planted by bad actors using generative AI.
On the capability side, I say hello _when you call me_ differently than _when I call you_. Anybody who knows me will certainly have a sense something is off.
Socially, we all should be used to the idea of calling back using official numbers, and not closing an agreement on the first call.
But this is a numbers game. I imagine this vector would be more successful on third-world migrant workers, than in the first-world economies.