*sigh* No, for the five millionth time, that is not the intent. The Kelvin timeline branched off from the Prime timeline; it did not erase it. It's nonsensical to think that the creators of the movies wanted to eliminate the Prime timeline from existence. CBS would never have let them do that, and the very fact that Discovery exists in what's unambiguously a separate timeline from Kelvin (because there was a Klingon war in 2256-7 when STID says there have only been a few minor skirmishes as of 2259, and the Enterprise is already in service in 2256-7 while the Kelvin version isn't launched until '58) proves that Prime still exists.
And yes, decades of time-travel fiction has brainwashed us to believe that altering history "erases" the original timeline, but that's physically impossible and logically contradictory. The writers of ST '09 chose to employ a more scientifically credible model in which the new timeline coexists alongside the old one, both because it's more scientifically up-to-date and because it lets both timelines coexist and continue to have stories told in them.
For that matter, there's already canonical precedent in "Yesteryear" -- when Spock goes back in time to restore his own timeline, he says he hopes Commander Thelin lives long and prospers in his own timeline -- which he would not say if he expected Thelin's timeline to be erased when he restores his own. It's implicit that the two different timelines coexist rather than overwriting each other. As reinforced by "Yesteryear"'s opening log entry describing the Guardian of Forever as "the focus of all the timelines of our galaxy."
As I've been saying, this is not true; there were always fans who objected to the perceived continuity errors in sequels like the movies and TNG, who refused to accept the redesign of the Klingons or the other reinterpretations of the universe. The change to prequels just shifted the topic of the objections. It didn't change human nature, the inability of some people to accept anything that challenges their preconceptions and assumptions.
Not to mention that some fans will attack any difference whether it involves continuity or not. When Voyager came along, there were vicious misogynistic attacks on Janeway. I'm sure there were racist reactions to Sisko when DS9 came along, but I think that was before I got involved in online bulletin boards.
In that case why did the Enterprise have to go back to 2063 to stop the Borg assimilating the Earth? Why did the Enterprise C have to be sent back to 2344 to stop the war with the Klingons breaking out?
That was exactly the same example I was going to use.
As far as Trek's history with this, the whole idea that an altered past has no effect on the present seems really arbitrary and sudden.
It doesn't matter by what method the time travel occurred, the fear and the results are almost always the same.
We see this happened again and again in the movies, on the show, in every series. Someone is always worried that the slightest interference will damage their entire reality when they return to the future .
The Borg went back into the past and assimilated Earth. Suddenly, the crew notices that humanity has disappeared and Earth has changed and history has been altered.
Only after fixing things does everything return to normal.
Sisko, Dax and Bashir were thrown back into the 21st century.
Gabriel Bell is killed before he can do whatever he did that ultimately brought about the Federation. When that happened, Starfleet suddenly disappeared. Everywhere, everything.
After Sisko managed to fix things and impersonate Gabriel Bell, everything returned to normal and historical records show a picture of Sisko instead of the real Gabriel Bell.
Nero came from the same timeline as Picard and Sisko and Spock. He went a one hundred something years into the past and destroyed Vulcan.
As a result if nothing was restored or prevented, TNG DS9 and Voyager should have reported that Vulcan was destroyed in the history books. Tuvok should have mentioned it.
I use to think there were two different different timelines two until I actually thought about it.
None of these things created an alternate timeline, it actually affected the Prime universe unless they did something to fix the situation.
It's the same universe!
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