The tweet by Jameson Lopp that OP is referring to:
https://twitter.com/lopp/status/1171847107243859968?lang=enI'm not really sure what you mean by the government and the people "crashing", but I disagree with your other statements. Fiat is still a better currency to use for businesses simply because of the stable value of the USD(compared to BTC at least), and because fiat is still far easier to use than cryptocurrencies in general.
Also, as a long term bitcoin bull, you don't really expect the current fiat system to be replaced by bitcoin "soon". It will definitely take a while. Bitcoin isn't even ready yet to use for-payments.
Fiat will be replaced by crypto currency but i dont think it will be bitcoin. Government want to control everything and even fiat money , bitcoin cant control by the governement so they will create thier own and will use blockchain technology to make a new way of payment before fiat currency fall.
If the winning cryptocurrency would be a cryptocurrency that the government can control, then what's the point of replacing the current fiat system in the first place? One of the main reasons bitcoin exists(along with most cryptocurrencies) is to have a currency that not a single central entity can control it.
It is like we're just moving forward towards the trend of technology. If the government will have its own crypto to be used by every individual, it has no difference between fiat currency. Centralization will only lead the point of having decentralization to waste if we still get to used the same process as we have on fiat.