Document signing is a good potential use case. The current transaction fee is $.50 [0] so that’s not too bad to securely sign a document.
There’s a separate issue of verifying and identity proofing wallets.
But I think blockchain actually helps solve the problem with pgp of trusting unknown identities and key exchange. Currently if a document is pgp signed by John Doe, I’ve got to figure out if it’s really John Doe and that’s a bit of work if I don’t already have John’s public key.
> I’ve got to figure out if it’s really John Doe and that’s a bit of work if I don’t already have John’s public key.
Maybe a dumb question, but assuming a scenario where you have a concept of "really John Doe", isn't there always some authoritative source on what that means that you could use to obtain John's public key (whether that's some user registry, direct contact with John, etc)?
yes there is, and that's why most blockchain projects that interact with the real world are doomed to fail.
Another classic exemple are those who wants to solve supply chain problems. To put it simply, the robustness or decentralisation of the database is not the reason why your inventory doesn't match what's in the warehouse. It's all human-related problem (eg. theft, losing shit, scanning the wrong item, being scammed by suppliers, etc.).
There’s a separate issue of verifying and identity proofing wallets.
But I think blockchain actually helps solve the problem with pgp of trusting unknown identities and key exchange. Currently if a document is pgp signed by John Doe, I’ve got to figure out if it’s really John Doe and that’s a bit of work if I don’t already have John’s public key.
[0] https://ycharts.com/indicators/ethereum_average_transaction_...