The Servers are not Down, it's just you can't log in. And Ubisoft have literally explained at the beginning of their post that this is sort of Degradation issue provoking this pop up message.
IK people have pointed this out, but going into offline mode does log you in. It's connecting to their servers that cause the problem. Still, I feel for yall trying to play R6S...
ITT: a bunch of whiny, entitled little children upset they can't play their video game. Relax kids, get up from the computer, go outside, read a book, go to the gym, and when it's fixed they will let you know and you can resume playing your games.