Guess who's dumb now
Vitalik has no idea what he is doing with ethereum. he doesn't even have any faith in its future and he has been clear about it from the start.
ETH is not designed to be a currency or anything like that. it is just a token for smart contract usages.
It's " just a token that is designed to work as a "fuel" to smart contracts" but this doesn't stop it from being a currency too. It's traded and it's can also be used to make payments just like bitcoin. come on, stop having a rigid mind.
Should we say Ether is not a form of cryptocurrency
no we shouldn't because it is a token.
can you use it as a currency? of course you can. you cal also use any other object as a currency, for example you can use CS:GO game skins and Dota2 items as currency, some of them even worth thousands of dollars! you can go to a restaurant and pay with one of these but that doesn't make them a currency!
similarly you can use bitcoin for smart contracts but you shouldn't because it is not designed for that! why do you think (pre 2015) ideas of Vitalik kept being rejected by bitcoin developers team? he was pushing all this on top of bitcoin at first...
ps. and lets not forget the big cherry on top, which is the fact that ETH is not immutable ever since they did that roll back....