I'm not sure that TPTB won't manage to eliminate cash altogether.
Every country is now on the path to a cashless society, just look at what the government in India just did.
The drive to a purely digital bank centered system is where they want the system to go.
However, as with all things human, ingenuity has created cryptocurrency and in the case of Bitcoin it is completely decentralized and out of the control of world governments.
The war for control of currencies is only just beginning.