Secondly, it requires the government not knowing that you own bitcoin, so they don't physically coerce you in to handing them over of confiscating your wallets.
If the government totally criminalize bitcoin, this will be a way most people's coin will be seize because nearly most bitcoin users are making use of it through IP addresses, only few are totally concerned about privacy to this extent and making use of VPN and Tor to bypass. Some people are even still making use of Tor wrongly in a way it can be leaked that they are making use of bitcoin.