For the near future, certainly not possible. But if bitcoin can last up to 25 years, I believe that bitcoin will replace the dollar. users of the bitcoin is always increasing, and certainly had a strong chance to replace dollar.
Bitcoin is nothing more than an alternative to fiat and other assets, what's so difficult about this to understand? Nothing beside the governments themselves have the ability to force through changes, and perhaps even replace it (which I don't think will happen in the coming decades). In order for Bitcoin to at least make a chance to reach mass scale adoption, it at least has to perform well as currency. Exactly that is something that it doesn't do (in the way that it doesn't outperform fiat when it comes to the currency aspect). Why would the average people then ditch their fiat currencies and hop over to something way less convenient as daily payment tool? Doesn't make any sense.