Do you know how vex can infect others and turn them into vex, the vex fluid acts as some sort of disease which constantly infects other species and planets through this. Someone can even touch the radiolaria and become vex days later. My theory on the reason that our favourite scientist that has a vex arm, or Asher Mir hasn’t died/turned into a hobgoblin/goblin is that the light is protecting him partially. Since the light can defeat basically any sort of disease, e.g. tetanus. The vex must have infected a species of alien and began the process of transforming that planet. Then continuing that process over and over. It’s pretty clear that the vex keep spreading as so long that there is a single drop of vex radiolaria in our solar system... The vex will survive and grow until the sun dies or even past that. But by then this war will be won...