I can't see it happening in the next 50 to 100 years. Perhaps after that.
Of course there will always be money around I suspect. Money will never go away like in ST TNG. It is just human nature to have it.
The problem with paper money going away is many if not most poor people still do not have bank accounts. They deal only in cash in many cases.
As an add on to this thread. Feel free to discuss any economical issue you forsee in the future.
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