I think its possible but in recent not possible to overcome the central Banks.The reason behind government won't let this thing happen, they won't permit any decentralized framework take over the banks and other than central banks is much imperative since we still require it to cash out our cryptocurrency, imagine if there's now not a bank at that point for beyond any doubt no one can change over their bitcoin or any altcoin into fiaJust think for a moment  if BTC overcome so fast how will manage the variable rates and retailers will not accept to early till they well trained and aware about Bitcoin.