Ethereum is potentially quantum-resistant, as is any Turing-Complete cryptocurrency platform/network/whatever-you-call-it. Since you can implement your own cryptography, you can use use quantum-resistant ones.
It would still be a crypto-world catastrophe if modern non-quantum resistant crypto was broken. Essentially, everyone would have to deliberately move their coins in one fashion or another from a vulnerable address/account to a safe one--and can you imagine trying to herd that many cats?
I agree.
I dont think we need to be too concern, bit when the NSA say they are concerned then I sit up and take note.
However, I do think the crypto-world will have to go though a period of upgrading to that of quantum resistant cryptography.
Actually a thought just occurred to me : I can see crytpocurrencies using this in the near future as a way of drawing attention to their token, eg CRYPTO NEWS FLASH: "DASH IS NOW QUANTUN RESISTANT"
Thanx for the input @smithgift