Crypto/blockchain is changing the structure of economies at the macro level and businesses at the micro level. When people talk about government control over various aspects of something I think its unrealistic to think that things will become decentralized to the point of anarchy. I don't believe that would benefit the world personally, but you are welcome to disagree. What it does enable is the ability to operate within a system that isn't manipulated by central banks and large financial institution.
As we've seen since 2009, the quantitative easing did reduce the short term impact of the economic shock that caused the recession, but the great majority of the benefit has been reaped by the wealthy. By wealthy, I mean those who own financial assets and don't live paycheck to paycheck. The stimulus has caused financial assets and real assets to appreciate, but real wage growth (where the lower-middle to lower class citizens derive their purchasing power) as been very stagnant until the last year or so. This is why the wealth gap has spread considerable over the last 8-9 years globally.
So by utilizing a monetary system that isn't manipulated by the wealthy, we can free ourselves from this aspect of oppression. It doesn't mean we'll have a world where everyone can commit tax evasion without being caught, and my opinion is that world wouldn't look very attractive anyway (again, some may disagree and that's ok too).
Governments will not be able to stop the innovation and maintain the fiat system based on game theory imho. The utility gains of crypto/blockchain are far to large. It would require a global agreement between all developed economies. But if that agreement was reached, which is a long shot on it's own, each nation would be incentivized to cheat in order to lock in a competitive economic advantage. Once one nation cheats, the rest will cheat so they don't fall behind and the agreement would fall apart.
To see an example of this, consider the restriction of the internet and how much of an economic disadvantage that would represent to a nation. There would be no way to compete. Blockchain is AT LEAST just as much of a utility gain for participating economies, so it will not be banned. I think to key to realizing the potential is creating a way to integrate the legacy and new systems so that participants can "slide" from the old into the new.