Nobody said not to touch Fiat, until adoption and fungibility are widespread, Fiat will have it's use. Cryptos are being hoarded because they are a better store of value, period. Once adoption and fungibility come along they will be used just like Fiat, and they are indeed a currency, the public has yet to see and accept that, those who are hoarding it are aware of that. That is why they are happy to exchange Fiat for crypto.