I am using crypto for receiving payments because many people likes it and pays using crypto but after year of active using, I think it will never kill real currencies because:
NO REAL VALUE
Nobody can guarantee value of crypto currency. It's not connected to stocks, real monetary system, real goods like oil, gold, etc.
HUGE ENERGY USAGE
To generate crypto currencies, we are using huge energy, more than small country needs. It's wasting of resources.
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