Fiat money is a type of currency that is not backed by a commodity, such as gold or silver. It is typically designated by the issuing government to be legal tender, and is authorized by government regulation. wikipedia
Ecash does not come into existence or is issued through government decree, so its not digital fiat.
Also, in theory at least, ecash is backed by bitcoin.
I'm not trying to change your mind. I have issues with ecash as well. I just think when arguing online, the right words are important.