That Sulu is gay in the Kelvin timeline and straight the Prime timeline implies that the Kelvin timeline diverged from the Prime timeline before Sulu was born, 3 years before Nero arrived. This establishes that the Narada was not the event which split the timelines - the Narada merely traveled through a wormhole to an already existing divergent timeline. This actually makes more sense than the official explanation, because Spock Prime’s ship travels to this same already existing divergent timeline which contains the Narada instead of creating a new ‘divergent timeline’ itself.

There. Another successful application of the Many Worlds hypothesis. My work here is finished.