Marketing speak bends the truth? Say it ain’t so!

and this requires devices to exchange the shared private key which is inherently risky.

There is some risk, sure. I don’t see how this would be any more risky than a TLS exchange. Obviously the exchange can be implemented badly, but if done correctly it seems like it would work with certs and send the key encrypted.

I think the bigger risk is the key sitting at rest on multiple devices, some of which are easily lost (cell phones) and could then compromise an account.

The US should lead the way by cutting 10% a year.