An operation with the scale of FFXIV can't just cut ties with their hosting service and ISP without giving them reasonable time to address an issue like DDoS attacks. The logistics of moving everything is complicated and time-consuming also. I've worked with hosting and ISPs long enough to know how long these sorts of impairments usually take and should take to resolve under normal circumstances. I'd start to ask questions about the competency of NTT's ability to handle DDoS attacks after cutting them some slack for few weeks, especially given that the NTT has proven that they can work around each attack within a few minutes. If the attacks lasted for much longer than they do when they happened, I'd probably be less inclined to be as patient but the responsible people at NTT seem to be getting on top of each attack and doing something about it right away.
Something else comes to mind. What if you are late for work by a few minutes for a week because there is construction and you have no history of lateness? Should your boss have a heavy hand and dock your pay or take other drastic measures? If you are a good employee, you'll leave earlier or find a better way to get to work and your boss will forget about it. If you are habitually late for weeks on end, then I'd expect your boss would look at taking corrective measures. I'm not convinced that NTT has proven that they can't get this resolved and that SE needs to find another hosting service yet. If this is still going on next week, I'll be concerned.