ZKPs have only become cheap and easy enough to do in the last few years, so of course Goldman Sachs doesn't use them yet. They'll be using them in a decade, for now look at startups. https://github.com/zk-passport/openpassport is one that is working today, worldcoin ID verification is another.

I carefully gave examples of where ZKP can be useful outside of blockchains.

> Like they don't use blockcrap for interbank settlements, asset tracking, notary, etc.

Yes. So far the only way to track real world assets on a blockchain is to have a trusted third party (or third parties) that connect whatever your blockchain says to the real world.

But if you have that trusted third party, you might as well have them run the database that keeps track of who owns what. No need for a blockchain.

ZKP is different in the sense that it's one of only a few things to come out of the 'crypto' world that has at least a _chance_ of being useful in the real world. One day. Perhaps.

(Cryptography in general is enormously useful. Have a look at HTTPS for one example. When I just say 'crypto' I mean specifically everything to do with the blockchain ecosystem. So far the only real applications of crypto / blockchains that I've seen are gambling (generously called 'speculation' or 'investment') and ransomware payments. Cryptocurrencies aren't even good for buying drugs on the black market so far.)

In any case, ZKP is still very immature. But we are very fortunate that the crypto-people are generously funding this area of essentially pure mathematics research.

[dead]