Goverments may amend a tax law which orders implementation of a tax to air that we breath. I think, they'll find a way. People will find a way in order to avoid paying tax for crypto money transactions. For payments, there seems no way to avoid a tax in future. Because gaverments may easily control companies which accept crypto currencies for their goods and services.
I think people who uses cryptocurrency cannot find a way to avoid paying tax if the government will start to accept cryptocurrency in the future because the government will not let us to earn money for free, that is why they will give us tax.