I do not understand why I should compare these currencies. The dollar is for the government, and bitcoin is for the people. So it was from the very beginning of the existence of bitcoin. And bitcoin will never replace the dollar
I guess no government will agree to that
The government money is specifically made to be used by the majority of population. And Bitcoin is a face-to-face and head-to-head competitor of any government money out there. Whenever a foreign currency (just an example) enters the local markets, the government becomes very hostile toward people using that currency instead of a local one. Bitcoin is no different in this respect. In fact, it is even more dangerous since it can be transacted without using local banks which is impossible with any other foreign currency