if too many people is using bitcoin then government will make rules to tax bitcoin transaction and maybe the government will banned bitcoin, but actually now we already pay bitcoin taxes, everytime i exchange my bitcoin in local exchanger they will charge few percent of my bitcoin
I think if the government still forced to give taxes to the bitcoin will not run both because someone could manipulate their bitcoin address because bitcoin is anonymous so that the government will not know if you have a lot of money in another purse? bitcoin tax will not be perfect
There is no way the government can track down every bitcoin address and tax them. Their only option is to rely on your honesty that you will declare your bitcoin income correctly. And that is a loophole you can always abuse. That is why government will not support bitcoin, because they cannot control it.