No I dont think that Bitcoin will replace the Dollar soon, because till now the most part of people worldwide still using fiat and also Bitcoin isn't yet supported everywhere online and offline, and not even legalized in some countries.
I also think it is impossible because Bitcoin needs the dollar and by extension other fiats in order to be exchanged and coexist but for it to outdo the dollar means it will be solo and risk being centralized.
Bitcoin does not need the dollar, right now the most powerful currency is the dollar and that is why every currency is compared to it, when bitcoin takes that spot then every currency will be compared to bitcoin instead.