Just as journalists (and I) were learning how to code.😢
O.K. I accepted the ChatGPT answer that it didn't know how to CoinJoin but after a few more prompts, maybe this has also changed since around 2021, I think I've learned that CoinJoin can''t be implemented because Hive's blockchain does not have UTXOs like bitcoin. Instead of deleting inputs and creating outputs for transactions Hive's DPoS only updates account balances with each transaction.
So instead of bitcoin's two options to increase anonymity crypto tumbling on Hive would be the only real option for anyone wanting to go from pseudonymous transactions to anonymous ones.