You don't know what fiat means.
You are describing yourself. You cannot project YOUR problem on anybody else.
The word 'fiat' first appeared in the English lexicon around 1630, stemming from the Latin 'fiat', which means "let it be done" as in an authoritative sanction.
Has nothing to do with central authority.
Yes it does. That is part of the definition of the word. It always has been.
Fiat means the currency has no intrinsic value. That is bitcoin. THINK
All currency has value. That simply means you can buy and sell with it.
All currency is three things:
1. It is a store of value. You can buy and sell things with it.
2. It is a unit of account. You can set a price with it.
3. It is a medium of exchange. You can mediate barter with it.
If a currency loses even ONE of these three characteristics, it is no longer currency.
Bitcoin is a currency. So is the FRN dollar (even when it loses value!). So is gold and silver. So is Yen (which has already crashed).
There is no central authority for Bitcoin declaring it's value.
A fiat currency has a central authority declaring it's value, like the FRN dollar or the Yen. For the FRN dollar, that authority is the Federal Reserve, acting upon the orders of Congress.
Obviously, you don't like Bitcoin. I don't either, but it's not a fiat currency. I already stated why I don't like Bitcoin.