Maybe. But as of now i think it's far from being possible. Yes cryptos at the moment are really famous but it's not yet implemented by the government. And since it has its own decentralized system, I think the government would find it hard to trace all its users. Maybe after long, long years the government will acknowledge cryptos if they are still existing by that time. Beside this I've read some article and it says there that it is impossible to replace the fiat of other digital cryptocurrency. It shows there also of how money dollars reserve they have and digital currency has just only few reserve so its impossible to replace it. Aside from that digital cryto is depending also on fiat. Without fiat, digital currencies are nothing.