Ok, let's say you have 100 Dollars in your pocket and go out and spend that 100 USD, maybe you bought a pair of jeans, get a bite or cafe somewhere and then take a cab home. Can someone really know what you did with your 100USD? the simple answer is NO.
Now, let say you have the equivalent of 100 USD in Bitcoin in your coinbase wallet, which required full ID identification to register. Now which is easier to trace the Cash you spent or the BTC you spend that registers every transaction in the blockchain, what do you think you are downloading when you install the Bitcoin wallet on your computer? you are just downloading every transaction that ever happened since the creation of Bitcoin.
So you are saying that coinbase turnsover all their data to the government?
Maybe yes, maybe no. I don't have proof to claim that coinbase is giving any date to the government, but i wonder why they need all that data in the first place.