Yeah, I am confused by the OP here.
That Blizzard retcons stuff, or Sylvanas’ character being assasinated is no secret and there isn’t much can be debated about it… but Sylvanas’ responsibility behind the Wrathgate or lack thereof is a 50-50.
And discussions raged across the forums back then to no solid conclusive evidence. Both sides made great points so Sylvanas having true responsibility behind the Wrathgate and plague is really the least shocking of retcons - IF it can even be counted as a retcon.