I'm not saying the old timeline wasn't erased I'm saying it still exists as a quantum reality where Spock and Nero DON'T go back in time were you paying attention to Parallels?
Oh trevanian and Anticitizen as to the it would be in character for Spock Prime to fix the timeline argument well the timeline wasn't exactly right at the end of Yesteryear and yet Spock wasn't trying to bend over backwards to save his poor sehlat, so there is a slight precedence here.
Parallels - deals with alternate realities
similar to the Mirror Universe, not time travel.
Yesteryear - ain't canon.
On the side of the fence where there is one timeline that gets changed, we have Operation: Earth, Tomorrow is Yesterday, City on the Edge of Forever, Yesterday's Enterprise, First Contact (the film), Trials and Tribble-ations, Endgame, etc etc etc.