When Blizzard says morally grey they mean that they wanna make you intrigued with the story and later lowkick you with a reveal that's just a cop out.
Sylvanas is morally grey, it's not that simple, just wait and see. She burns down the tree because a random Night elf made her sad.
When Blizzard says Morally Grey they just wanna get you intrigued in the story and to later lowkick you with a cop out that's just not even grey...
Sylvanas is morally grey, it's not that simple, just wait and see. 9 Months later she burns down the tree because a random Night elf made her tell her backstory.