We've desperately needed secure identity verification for business callers for years, so we can start the decades long process of changing people's instincts about it.

There's no good reason any business should be able to contact me without whoever is calling cryptographically proving they're that business and my phone showing the name and logo from a copy or mirror of an official database.

It should just be a standard part of business registration processes.

But for which country, state, province, or city?

Put in the hierarchical angle, and we're kind of back at domain names.