Sylvanas died because of Arthas and her revenge was taken from her when the heroes killed Arthas on top of ICC. She jumped of ICC just to be confronted with Arthas yet again in the maw.
Sylvanas her entire end goal is to get a 1 on 1 again with Arthas.
Think about it. Arthas is in the maw and we know due to something every other soul is being fed to the maw as well.
We had no clue no one did but Sylvanas knew this gets close to the jailer in order to draw attention to this by us.
She opens a portal to the shadowlands by putting Bolvar in his place. And now we outsiders are free to travel to the Shadowlands too. Bare in mind we are still oblivious to all what happened there but Sylvanas leads us there with these super obvious bread crums.
If she actually had any intentions to gain more and more power by feeding souls to the Maw she wouldve let the link between here and the Shadowlands closed.
Now we go to the Shadowlands break the curse thats been sending everyone into the Maw. Including all the Night Elves from burning the tree. (If following her plan to âstopâ her wasnt enough motivation for you).
Now I hear you scream but Sylvanas would never do such a 4d chess play just to help anyone.
Now here comes in the Arthas part she would finally have her moment to face Arthas once the seal around the maw is broken and we can all enter that realm.
Honest past this point everything could be up for more speculation maybe it was a 4d chess play from the Arbiter to get Sylvanas who could operate in the land of the living to get us there and âfixâ things but who knows.