I think a new fiat will probably be born in crypto. Bitcoin is not the new fiat, but it may be the new gold. The reasons that fiat will be digital are many; but there is definitely a war on cash going on (see India bans large notes, notice the digital revolution even withe cards before crypto). Banks don't want to lose savings deposits when they finally start pushing negative interest rates to try to kickstart the economy for one. There are also a number of ways that digital currencies and smart contracts can facilitate commerce and therefore also kickstart the economy. Just the implications of the technological abilities alone that are coming to light are enough to put money bags in the eyes of the government, big banks, etc., so if anything I think they see it as an advantage not a threat. This is becoming more and more clear as we see Jaime Dimon rescind his comments and even allow a spokesperson to admit they are interested in Bitcoin now...Putin endorses Ethereum...the IMF talks about creating a blockchain, etc., etc., I think large institutions will not directly oppose BTC/ETH but endorse and create others that have the intention of dominating over it.