Going cashless is a positive and favourable reform as far as decentralized currencies are accepted for day to day minor transactions. If we rely on government currencies after going cashless, I wouldn't consider it to be a good circumstance for the masses.
It will be a loss of freedom if that happens. The central authourity will have access to 100% of the transactions taking place and for every transfer wether minor or major we will have to depend on a third party to let it through. We will be sacrificing on our liberty to make direct and independent transactions without government intereference. Also it will become much easier for the governments to cease our wealth and enforce undue taxes.
RE: A world without paper money