Might be accepted by most of the countries? if the cryptocurrencies would be accepted by most of these countries we will have a massive wolrdwide and we are the early adopters would be millionaires to billionaires,that is the thing that cryptocurrencies need to have, a full adoption or atleast to be accepted by most of these countries.
They are already accepted by maximum countries across the globe, but just as an asset and not a currency. Cryptos and their exchanges are being regulated in many countries now.
There will surely be mass adoption of cryptos, but it will only be as an asset(store of value) like gold and stock markets of companies and not as a currency. Government will never accept a decentralized platform based coin to prevail as a currency.