And now we've hit the critical point. The history only works if the emperor seriously believes "If I close everybody eyes and ears, chaos can't hurt us!".
No, no, no, no, no, no, no, no, no, no, no, no, NO, NO, NO, NO!
Every one of your posts to date in this thread has been uniformed and trollish, but the willful ignorance and blatent ignoring of canon in this statement is absurd to the point of incredulity. Your post history as a whole is a fractal of wrongness, but I will address only this one point so as not to go overboard on a rant of mythic proportions.
The Emperor was working to kill the chaos gods, and actually doing a pretty good job of it. The chaos gods are fed primarily by two things: the emotions of sentient beings, and active worship. The second one being the key one that feeds them more, as the levels of emotion required to feed them substantially is orders of magnitudes greater compared to how much outright worship does.
Given that chaos gods/deamons in general, and tzeench and his ones in particular have a history of disguising themselves as religious figures in order to syphon off worship for their own empowerment, the emperor was stamping out relegion specifically to deny the chaos gods this source of food, and also to calm the warp. This plan of his was working. Know how we know this? 30K ships didn't require a giant psychic warp lighthouse navigate around the galaxy. Navigation in the "present" without the light of astronomicon is almost impossible.
So when the Emperor went after their food sources, the chaos gods had to fight back before they got starved out completely. The fact that they were able to do so doesn't make the Emperor's plan stupid, or even invalid. Especially since it was working. He just happened to be the single worst father ever, and so his sons didn't turn out too well, and were easily corruptable by chaos.