In the case of the Bitfinex attack there isn't even the slightest suggestion that some sort of "hard fork" would be offered by the Bitcoin Core developers
Opinions?
To be fair, one Core contributor did make a slight suggestion which would certainly result in a fork. You can't really say this was from
the Bitcoin Core developers though (other Core contributors were quick to disagree with maaku, which caused some backpedaling from him).
https://www.reddit.com/r/Bitcoin/comments/4vupa6/p2shinfo_shows_movement_out_of_multisig_wallets/d61qyajAnyway, it's certainly nothing like that which came from the Ethereum foundation after the DAO coding fail (I personally don't think it's correct to call those events an "attack", after all code
was law).