How does it make no sense assuming that the Titans are most likely going to be the antagonists? Iridikron constantly poinst about how the Titans don't actually care about the inhabitants and only care about claiming the World Souls for themselves, and rightfully predicts that the Titans will not come to help the mortals defend themselves against Fyrak (which they don't).
Iridikron has not been antagonistic towards us at all. He uses void magic, but he literally said that the only reason he is allied with Xalatath is to bait the Titans to come to Azeroth. The Primalists whole MO has been to keep Azeroth as a World Soul rather than let it be turned into something that it's not.
There's too many "Worldsoul =/= Titan" and free will angles for that approach to be dismissed. War Within has us pissing off the Titans by "freeing" the Earthen, and they literally send Constructs after us.
It's not really a plot twist if the plot has been working towards this for three expansions.