It's literally childish. In the developmental phase, children are supposed from growing out of having an absolute view to having a more ambiguous one. Examples of absolute views are "mom is the person best in the world," and "mom is the worst person in the world." In this case, trolling or firmly having an absolute view that Azshara was good.
It's the same sort of behaviour you see from people unironically calling Sylvanas competent when in reality she's as dumb as wet cardboard and only seems competent because everyone else is dumber. https://www.mmo-champion.com/threads...sed-brilliance