Figured I'd add my share of the troubles. Though I am not with Spectrum or any of the previously mentioned ISPs. I used Conway Corp here in Arkansas. All of this lag started around midday today, the 13th. It was perfect just the other night. No issues at all. I'm sure it is not my ISP given my internet has been flawless all day. It is only ffxiv I am having this issue with.
Through a tracreroute, it seems just like with everyone else my issues start at the NTT IPs.