See, this little part is extremely irritating to read. Do you know why?! Because it's absolutely wrong, in a lot of cases.
If in the terms of service they wrote that you have to kill a kitten every time you want to log on, would you?! Heck, could you?! Would they be able to deny you service if you fulfilled the requirements otherwise?! If even one answer is different than 'no' for someone, then that person would need to see a specialist. And probably their local prosecutor if it would be for the first one...animal abuse is illegal in a lot of places of the world.
If a clause in any contract (terms of service included) goes against the letter of the law, it is invalid. They can write anything and everything they want in terms of service. More, I'll tell you this. Many publishers of MMO's, especially F2P ones, KNOWINGLY and PURPOSEFULLY add clauses that are invalid (the "you will not take X to court" variation being the prime culprit), just cause it will stop people that don't know the law, while it won't really hurt them against those that do.
If a law would obligate them to pay compensation, even if it is one of the things they wrote about in terms of service as exceptions, they will need to pay compensation if taken to court. Simple as that. The clause being in terms of service would be absolutely no argument at all and bringing it up could actually lead to a fine, instead of help their cause.
However, as I said, this is LAW DEPENDENT, and it does NOT apply to all people, as the laws where they live apply, not the law where the servers are, where Square Enix is located or anything else on their side. And some countries offer more pro-consumer laws than others.
It also does not apply at all, anywhere, if the issue is entirely on the ISP or any other middleman. How many people are affected or are not affected doesn't matter, only the source of the cause.
All in all...unless there would be many people gathering up for a group law suit, this is all moot, because practice shows that the losses, even on a won case, would absolutely not exceed gains when the matter is over such amounts as are brought up here (monthly subscription).
Now, don't get me wrong. I am neither telling anyone to go to court or anything of the sort. I am merely trying to inform you of the reality as it is seen by law, not by personal feelings of what is right or wrong. Cause law not always follows what one would call "common sense". And sometimes, like in this case, for a very good reason. You wouldn't want people literally sold into slavery just cause they ended up signing a contract that would enslave them, would you?! That's why law needs to trump over personal contracts, even if at times, it causes a completely innocent party to pay the price.