Hello!
Recently, I have been suffering from frequent Error Code 90002 disconnects when playing FFXIV. They have rarely been an issue for me in the past, but ever since the initial recent DDoS Attack (May 22) on the NA Data Centers they have developed into a consistent and frustrating issue, even after the "Recovery" updates (1,2) have been posted on the Lodestone. It does not seem to matter what type of Duty or activity I am currently engaged with in-game when the disconnects happen. They have occurred whenever I've been inside of battle instances, in the open world, and even when I was simply idle in the game. These disconnects don't seem to happen at specific times either, but roughly happen every 1-2 hours of playtime. However, other than the disconnects, I am experiencing no other issues with the game (no in-game lag, stuttering, etc.) and am able to reconnect to the game servers fairly fast. Even still, they are severely hindering my enjoyment of the game.
As far as troubleshooting goes, I have already followed all of the steps listed both on the relevant FFXIV Support Center website topic as well as the ones listed in a post by a GM in a recent similar thread. So far none of these changes seem to have made any improvement to my situation as I am still encountering random, frequent disconnects when in the game.
I just find all of this to be extremely suspicious considering these disconnects only ever became a reoccuring issue for me after the recent DDoS Attacks confirmed by Square Enix. Any and all help would be welcome, even if it is simply an acknowledgement that the issue is not on my end and instead is something outside of my control like my ISP or a problem with a specific node along the route my connection takes to the game servers.
UPDATE (5/26/19 9:53pm ET): Over 24 hours later and the issue is still persisting, even after more trial & error troubleshooting on my end. No other online game or applications are affected. I still only receive the disconnects when playing FFXIV. I've since tried playing the game through a VPN to see if having my connection routed differently would change anything, but when doing so I would instead occasionally receive 90006 error code disconnects in place of the usual 90002 ones.
UPDATE (6/1/19 5:14am ET): The issue is still persisting as it has been for over a week now. I recently called my ISP and had them send a technician to make sure the issue wasn't with my home network. The quality of the signal both coming into, and inside of, my house from was confirmed to be fine. Just to be super thorough, the technician even replaced some old wiring in my home and set me up with an entirely new modem. Since then, the frequency of the disconnects has gone down but they still happen. The persistence of this issue has taken a large toll on both my patience and sanity.
UPDATE (6/5/19 5:46pm ET): It's still happening... 
(Included below is a traceroute from my PC to what I assume to be the NA Aether Data Center):
Code:
Tracing route to 204.2.229.9 over a maximum of 30 hops
1 1 ms 1 ms 1 ms 192.168.0.1
2 22 ms 14 ms 10 ms cpe-065-188-128-001.triad.res.rr.com [65.188.128.1]
3 92 ms 31 ms 24 ms cpe-174-111-101-104.triad.res.rr.com [174.111.101.104]
4 15 ms 13 ms 11 ms cpe-024-028-252-032.triad.res.rr.com [24.28.252.32]
5 22 ms 16 ms 21 ms be34.drhmncev01r.southeast.rr.com [24.93.64.196]
6 28 ms 31 ms 30 ms bu-ether15.asbnva1611w-bcr00.tbone.rr.com [66.109.6.80]
7 26 ms 18 ms 18 ms 66.109.5.117
8 20 ms 19 ms 18 ms 38.142.221.105
9 20 ms 22 ms 19 ms ae-58.r06.asbnva02.us.bb.gin.ntt.net [129.250.8.121]
10 22 ms 24 ms 23 ms ae-2.r23.asbnva02.us.bb.gin.ntt.net [129.250.2.132]
11 85 ms 90 ms 92 ms ae-10.r22.snjsca04.us.bb.gin.ntt.net [129.250.6.237]
12 95 ms 94 ms 98 ms ae-19.r01.snjsca04.us.bb.gin.ntt.net [129.250.3.27]
13 90 ms 94 ms 98 ms ae-4.r00.scrmca02.us.bb.gin.ntt.net [129.250.7.57]
14 98 ms 90 ms 91 ms xe-0-1-0-1-1.r00.scrmca02.us.ce.gin.ntt.net [129.250.195.46]
15 95 ms 99 ms 94 ms 204.2.229.234
16 95 ms 89 ms 92 ms 204.2.229.9
Trace complete.