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?
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I still think replacing the dollar or paper currency with bitcoin is not the best idea.
There are certain roles in which paper money is more efficient in comparison to electronic money.
Economies need things like yard sales and second hand markets for cars, bikes, motorcycles, boats, clothes et al. Cash is the most efficient and best method of fueling things like yard sales and the buying/selling of second hand goods.
People might consider how they would sell their used car, used computer or 2nd hand goods if cash were outlawed. Its much easier to sell something for paper fiat than it is to sell something for bitcoin.