There is also the possibility that the attacker considers Ethereum a "shitcoin" and wants it to die. I heard someone claiming to be the attacker came into slack and said just that and is offering miners a rather large bounty to not accept the soft fork. I don't know if anyone can verify if it was the attacker or not, from what I've heard he really doesn't have a way to prove it, but I don't know about that. If this is true and the miners accept his bribe, he gets a much larger bounty.