If I pay bitcoin tax, where is the anonymity? It means the government knows where I live, my wallet address, probably the exchange I use and the amount I used in the exchange. If the government should know that much then they can control the use whenever.
I don't think it means any of that. All you have to do is report that you bought them, then spent them, and if you took a loss or made a gain. Just like you do with fiat. Hell, going along with the system and reporting all of your bitcoin transactions might even be a good thing. It could show the government that this thing is for real. And since it's digital by nature, keeping records will be easy, there are already a lot of services out there that help you with it.
It's not necessary to tell them that you are earning bitcoin because time will come if your country is not yet regulated about bitcoins, the government are surely making rules to regulate bitcoin, and when the rules will come out, we have no option but to comply with it, it is not voluntary anymore but compulsory.
I just wonder how many reports I will have to make while trying to give the government my money.