What do you think about my Star Trek theory?

This theory is about the creation of the Mirror Universe, and when it split off of the main timeline.
In “In a Mirror, Darkly”, an episode in the series “Enterprise”, Zefram Cochrane, after his successful warp flight, is shown killing the Vulcan landing party, and taking their ship by force, thus taking the first step towards the Terran Empire’s violent expansionism, and creating the Mirror Universe.

In the film “First Contact”, the Borg travel back in time to prevent Cochrane’s first warp flight, forcing the Enterprise E to follow them back in time, to stop the Borg’s plan, and ensure Cochrane’s success.

Later in the series “Enterprise”, in the episode “Assimilation”, recovered Borg technology and drones are found from the crashed Borg sphere, establishing the Borg incursion as definite history.

In the Voyager episode “Relativity”, Seven of Nine refers to the Borg incursion as a “causal loop”, in which the Borg attempt to alter history is the reason the original course of events occured in the first place.

Both episodes thus indicate that in the main timeline, the Borg incursion always happens.

My theory is this:
The Mirror Universe timeline was created, because the Borg never tried to prevent Cochrane’s warp flight, therefore the crew of the Enterprise E never went back in time with them.
Which means that they never primed and prepared Cochrane for his first contact with the vulcans by telling him of the future, in which humanity eliminates poverty, disease and war.
Cochrane thus went into first contact alone, full of the paranoia and fear he would naturally have felt a mere 10 years after the end of World War 3, resulting in the violence that led to the formation of the Terran Empire.