It's the government trying to enforce their opinion of who should own those Bitcoins, thereby taking power away from the owner that the network has decided on, which would be "whoever has the cryptographic keys".
This is where I may only be a 'partial' member: My feeling is that Bitcoin (not all cryptocurrencies) was about removing Fed/Gov control of the currency. It takes no position against law enforcement of direct currency theft - outside of what could be construed as the theft of currency value by quantitative easing / gifting bailout money to banks, etc.
Bitcoin, specifically, has always had a public ledger too, so start-to-finish transaction tracking is part and parcel.