I don't think so, maybe the the goverment won't agree that bitcoin will replace dollar because first of all bitcoin was not created by the government. We can't say when bitcoin can consider a real money because we can only earn it in the internet. Maybe one day bitcoin can replace dollar someday.
i dont think so bitcoin can ever replace dollar. logic is simple it is decentralized, it doesn't have any control from government side. dollar is good at its own place and btc is good at its own way. replacement of either thing is not possible. what we can see instead is more number of users in the btc which will sure give us the best monetary worth.