I'll clear all the FUD : Ethereum wasn't hacked at all. That was just The DAO. There is not consequence on Ethereum at all.[/b]
Then, to reply to OP, that's quite simple : the halving. That's what's draining all the altcoins for more than a month.
So why they want SF, HF if Ethereum was not affected?
That's a kind of roll-back to cancel these transactions. Since The DAO was funded by ethers, Ethereum can do something since that's still its currency.
Lets tell the brutal truth.
Since some of the Eth devs and leadership are most likely amongst the biggest DAO bagholders and stand to take a massive loss they used their privileged position to roll back history and save their own bacon. Most likely at the expense of every person who believed in ETH....
Sorry but changing history and rolling back the blockchain has never helped any altcoin and i suspect it will kill ETH too. I recommend dont be a bagholder