That was a long article but I was able to read briefly with little understanding. Government overrules all including the decentralized and centralized currencies. Believe it that if that if governments in the whole universe want to fight against decentralizations, they'd definitely trap it down by banning every centralized currencies tied on them in the exchanges.
Think about how many people in the local societies are basically accepting crypto currencies for payments if not mostly for investment and trading with an exchange of the fiats which is governments owned control.
The government could decide to ban decentralized currencies in its state to save their own central currency. The truth is that the decentralized currencies could function not in the way of eliminating the fiat and then gradually the wide range of adoptors in the universe could decide the appreciation of private currencies due to its potentials to assist the growth of the economy while the fiats may remain valueless. Then, the end of economy war of inflation would be eliminated.
The government has great control over the traditional financial system. And in theory This authority can be used to reduce the role of the financial schemes by attacking the intermediate business agents through which their schemes are operationalized. But what you pointed out, Decentralized currencies don't aim to replace fiat currencies entirely. They, however, offer an option that can be run simultaneously with the traditional financial system. This offers more options for choices on payments and investments.
While financial institutions can contribute positively to economic growth and provide new financial opportunities, they are in part the consequence of the larger social environment. Fiat currencies and government policy will continue to play important roles. Evolution into a fiat system with emerging technologies might well create an element of balance between these classic systems and new ones. Each system will influence and shape the other.
In summary, whereas governments have great control over the financial system and can impose their will once the financial institutions are established, But such new mechanisms do not defy the existing currency system. Such coexistence will assist in fulfilling those mechanisms This further leads to a more diversified and dynamic economic environment.