Part of what is wrong is simple transfers of coin out of coinbase.
Coinbase does not know where the coin goes so they show it as a cap gain or cap loss.
but if you moved it to your core wallet it is nothing a wash and coinbase reported the transfer as a liquidation thus causing a cap gain or loss.
I still think that it is coinbase fault as transfer out should not be a liquidation by default.
If I send btc to coinbase, do they consider it a BUY?
If yes, then it is ridiculous and a REALLY bad accounting standard.
Example: Say, I send 1 btc to coinbase when the price is 15K. Now I am withdrawing the same 1btc at 9K.
Do they think that it is a $6K loss? If they do, then they are negligent/in error.