Blizzard has just been retconning and whitewashing to make Illidan looks like he has been good and right all along. That expressed itself through Xera's narrative which made us to be those who were wrong when we weren't before. It's why I can't just take this seriously.
It was made so that Cenarius rejected Illidan when it was originally Illidan who walked away himself due not having enough patience. The Ravencrest event was changed to be that Illidan had no choice but to commit those crimes when it was originally that Illidan just drained other mages for no reason other than to fuel his display of power. The event of stealing the Dragon Soul from Neltharion's lair may have been retconned in the chronicle to be that Illidan was the one who stole the DS through his own effort when it was originally Malfurion who stole it from the lair and Illidan with Azshara's men took it from Malfurion. The list goes on.