Wrong. Fiat dont really need bitcoin. Of it does please provide some proofs that it does need it. I havent read an article like and I would love to see it until the end if there is one.
Fiat is what people need. This is the traditional money that people needs. One of the basic need is money, all people cant live without it. this is the basis of one's life statis in life. Nothing can ever replace fiat. Yes!and even bitcoins will not ever replace fiat. Bitcoin is a digital currency that we are using in buying some items online, sending money online, pay bills online but at the end; if we will cash it out, it was still converted into fiat.
We are just awakened with fiat but if we are awakened with bitcoins then we will also say that bitcoin won't be replaced by any new currency.
But with these days, it is not going to be an easy thing for some currency that will replace the usage of fiat.
The adoption is still far from the expected for this year, maybe we will expect more for next year.