I don't see how it really could be. I think the writers should have said Spock went to a alternate universe and changed that time line. Before the Narda even changed anything the Kelvin was way more advanced then ships of Kirks Era(i.e. Viewscreen in glass). I think the writers could easily have just said Spock was thrown into a alternate universe and changed its course rather than a universe that was supposedly supposed to be exactly like the Star trek universe before it became a alternate universe offshoot. I mean there isn't one thing in the NuStar NuTrek universe that is anything like the original in look or character, (Maybe almost Bones but that's it)
I don't get the point...
the reboot is a quantum reality.
'the writers should have said Spock went to a alternate universe and changed that time line.'
but in some way, they did and that's what happened.
Technically, yes Spock prime and the Narada created this reality when they went back in the past and modified the course of the timeline. Time travel essentially created a parallel reality (=different=alternate) instead of changing the tos one (that still exists parallel to this one) ala 'back to the future'.
But the thing is, the universe doesn't have our same (and limited) concept of
time and space so, in some way, it might be also correct to say that this reality had always existed parallel to tos and it's possible that even some events before the Kelvin accident happened differently and thus the so called butterfly effect created by the Narada changed some things
retroactively too.
Perhaps my interpretation is too simplistic and confusing but I think that from the universe's pov, so to speak, that is on a different scale than ours, there isn't really such a thing as past present and future the way
we intend it because, in some way, everything exists in the same 'moment'.
That's how you can time travel and jump from one reality to another or 'visit' the past, the present and the future of one..