Unless something else replaces Ethereum as the leading marketcap for smart contracts, then Ethereum will recover as Bitcoin did. Litecoin apparently lost its main raison d'etre which was those who were pumping BTC to $1200 needed a highly liquid coin to exit into and it had served as a home for displaced GPU miners when Bitcoin ASICs appeared.

This is assuming there isn't some insoluble technical issues, such as this one I opined about:

The only way it is fixed is by the ecosystem maturing and having a wide diversity of smart contracts (many of which have been well vetted) so that the failure of any one of them can't impact the ETH price significantly. And I think also Ethereum might have a problem where bad contracts can infect other contracts, so that may prevent the ecosystem from ever being NOT TOO BIG TO FAIL (I need to research this more).