Just to put minds at somewhat of an ease, I'll quote a snip from the e-mail:

We are sorry to hear that you are having lagging issues with FINAL FANTASY XIV: A Realm Reborn, and we understand your frustration regarding the issue and are sorry that you feel this way.

Thank you for letting us know that you will contact Sky. We are working on resolving the problem on our end in the meanwhile and hope that the issue will be resolved soon. We will contact you via email again with regards to your escalation as soon as there is an update for you.
So at the very least they know of it and are looking into getting it fixed, it's just a matter of when.