That's not crazy and is entirely, 100% both plausible and possible. In the books of sorrow, Auryx, Savathun, and Xivu Arath killed each other hundreds of times, becoming more powerful each time. For them, killing each other is an act of love and affection. When it came that the individuals' power was not enough to feed their respective worms, Auryx killed Savathun and Xivu Arath in their throne realms, giving them their first real death. With the power he gained from killing his sisters, he went on to kill the worm god Akka, and become the Taken King, Oryx. Being that it was a true death (because they died in their throne realms) they did not return. Until Oryx embodied the aspects of his sisters, cunning and trickery. He was able to revive them by embodying them and their ideals and aspects through an act of war (specifically against the Ecumene and Dakua Nest, if my memory serves me correctly). Fast forward to TTK, we kill Oryx on a part of the Dreadnought that is not part of his throne realm, and he returned in his throne as the giant boss in King's Fall. We kill Oryx in his throne realm in the raid, giving him his first real death. Therefore, being that Oryx has died a true death, it is plausible that Savuthun and/or Xivu Arath could revive him by embodying his aspects in an act of war. Personally, I do not believe that to be the case. I believe we last saw Savathun leave this dimension on one of her War Moons, and that was when she and Xivu Arath were revived, potentially hundreds of years ago. Judging by some of the context in d2, I don't think Savathun is the leader of the Taken, I think she controls them through Quria, Blade Transform, a taken hydra gifted to her by Oryx. The taken can technically "take" by transferring the blight to living entities, which is how we got the taken Red Legion soldier in the ps4 strike. Therefore, I believe Savathun's ambitions are much higher than reviving Oryx. She likely wants to take his place instead.