Captain Robert April wrote:
Nero's appearance altered history, and it cost billions of lives on Vulcan.
How can you honestly argue in favor of that level of destruction?
Because restoring the timeline to TOS would be a death sentence for Romulus and Remus in 2387. Vulcans wouldn't want their world to live at the expense of two others, even those of their enemies.
Kirk, Pike and Spock Prime know what's gonna happen. There's a chance the Romulan homeworlds will can be evacuated by 2387.