Popular opinion is that she is getting redeemed next raid or sometime shortly after it. I very much doubt it, her slicing Anduin with Shalamourne was the last final straw for her. It's the sign that she's finally truly broken with the last vestige of her mortality and morality.
It's also a sign that they are finally doing away with the last Warcraft 3 character. Yes, I know Tyrande is around, but frankly they neutered her and Night Elves in general when WoW launched and Jaina got her real closure in BfA.
Moving forward the morally grey leader/cult figure is going to be Azshara.