I don't think it is possible for now for fiat currency to be crushed,
Are you actually that lazy to read few posts above yours? There is more than enough of evidences and proofs that some flat currencies are dying and suffering with inflation.
It is very difficult or even impossible to imagine that the fiat currency will collapse in the blister it is widely used in countries and a lot of governments are supporting the fiat currency since from the start. so it's very hard to crash.
It won't collapse but it become worthless.