I' ll take bitcoin as an example.
Is it mandatory that the value of all bitcoins is equal to the value of the world economy?
Can this value be archived before all the bitcoins are mined?
When I buy bitcoin someone will take my dollars.
So how can we technically replace all dollars with the bitcoins?
In the end will there always be someone with only dollars in their pockets or am i wrong?
Dollar belongs to Us which has the biggest economy in the world. They don't have have to depend on another form of currency and the country's government will maintain monopoly over cash so bitcoin taking over cash is note exactly possible besides it's not stable either, it's better off as a currency used for earning money rather than replacing dollar.