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So far it is true, they can only do that and can't seem to manage beyond that. So far I feel optimistic that Bitcoin will be even more profitable because the government has opened its eyes to regulations and even collect taxes. Even if in order all transactions can be tracked if ever transactions on exchanges and banks in the form of fiat. In fact I have read if the BTC Mixer service from Coinjoin has also provided support for transactions suspected of money laundering.
Withdrawing taxes on cryptocurrency users will certainly increase the income for the country. it only takes time, Bitcoin or cryptocurrency becomes an important part and becomes the future transaction technology. The regulations given by the government will not be complete.
A lot of positive support has come that makes transactions in cryptocurrencies even better, as you said about the Bitcoin Mixer Coinjoin transaction which is willing to open its user data for those who are indicated as money laundering. But this will remain private.