In the trilogy from Knaak (please, no jokes that we just have to ignore any of his work or something like that), the Old Gods tried to seek the passage of time so that Sargeras could enter Azeroth and free them, after which they would kill him. But in the new lore, the Old Gods have no chance against Sargeras, he would have destroyed them in seconds. And they could not have been unaware of his power, because they clearly remember how Amantul tore their brother out of the ground and split them apart. And we cannot say that this trilogy is non-canon because we saw Brox and Rhonin in Illidan's memories. So what happened? Why would the Old Gods try to let Sargeras in if he could kill them easily?