They Also posted this after that, which gives me the impression that they think the issue is resolved

https://na.finalfantasyxiv.com/lodes...043842f3e43e19

"We are pleased to announce that the login technical difficulties with the instanced areas on the Aether data center Worlds have been resolved.

We apologize for any inconvenience caused, and we thank you for your understanding.

※The technical difficulties with the Adamantoise World are still being investigated and addressed.
Please follow the links below for details:"

[Aether] Adamantoise World Technical Difficulties (May 15)
https://sqex.to/eMIGg

[Aether] Instanced Areas Technical Difficulties (May 15)
https://sqex.to/wE58F

[Date & Time]
May 15, 2022 6:50 a.m. to 7:57 a.m. (PDT)

[Details]
- Unable to log in to Aether Data Center Worlds.

[Cause]
Server Setting Issue

[Affected Worlds]
Aether Data Center