From many months i am thinking about what if " we remove fiat system , and change things into crypto " .. What are the main difficulties we will face ?
1. Internet every where is not yet done.
2. Awareness with Crypto ( but its not a big thing, as most are aware of how to use currency. )
3. Bitcoin is only 21,000,000 and world population is more. ( This can fix by other altcoins same like USD/RUB/CNY etc )
What other difficulties we can face ?
There are 2 difficulties actually that you haven't mentioned.
Another difficulty that i can see happening is when we already become a cashless society, then we will have banks that run the crypto scene. And when this happens we are doomed. Just think if somehow the government hates you, all your crypto gets frozen amd takem from the government. And even if you have cryptos you didn't declare, you won't be able to take advantage of them since smart computers someday will be able ro check every aource of any transaction and if it finds you, it will also take everything you have left of your undeclared cryptos. And authorities will come at you and lockong you up for breaking a law that the future government in a cashless world made.
Another is a possibility of having hackers hack the main servers that control all types of cryptos and you can only guess what'll happen next.