From my research, while there are "defenses" against a DDOS attack, they are preformed by the ISP and not a company like SE. Even then, those defenses don't stop said attacks, merely try to mitigate some of the effects. The main defense is how you respond during and after the attack. And if your company isn't even the target of the DDOS, but merely an incidental victim due to your ISP being the actual target? Then there is literally nothing you can do beyond contacting the ISP.

So again, with that in mind... Just what do people expect Square Enix to actually do to stop all DDOS attacks on them and their ISPs?