> It boggles my mind that we've had public key cryptography for fifty years and we're still not using it for payments. Never mind blockchains, just upgrading the banking system to use public keys would be a huge improvement.

This ignores the number one lesson of PGP - key management is hard, up there with naming things and cache invalidation. I honestly don’t see how public keys, which are vastly more complicated to use and store than passwords, would be an improvement for the general, non-technical public when getting them to use long, unique passwords is already a challenge. You have to copy over or update your public key with each new computer you get, assuming the account owner even has a permanent computer. What about accessing your account on someone else’s computer in a quick pinch, or on your phone? Coupled with the fact that keypairs would be unable to be force reset (assuming you want to use them to their full potential) unlike passwords, and it would be a disaster.

I will say that minimizing the sensitive information sent for payment with crypto is a huge plus, as the merchant no longer needs to handle the card information to send to the payment processor, but can just accept the transaction hash (with some sort of signature of course).

This also doesn’t really address the issue that Coinbase will still send your info to ICE, of course. Not that banks are any better. But cash is!