Tax law is dependent on your country and locality. Recently in the United States, the IRS has declared that Bitcoin is to be treated as property, not currency, for tax purposes. All income in the US is taxed, regardless of what form it takes. If youre paid in bitcoins, youre supposed to pay taxes on your earnings at the BTC/USD exchange rate when you receive payment.
Is it a good decision or bad?
I think it's a good thing to pay bitcoin taxes if your country has these rules, in addition to avoiding violations of the law, paying taxes on bitcoin will show that bitcoin can also follow the rules of a country, and of course, that thing will change the bad perception of many people to Bitcoin so far.