So, I just got my copy of the Lower Deck's Handbook (it's AMAZING) but one of the sections of the handbook goes into the legacy of the ships to carry the name Cerritos. (Think along the terms of the ships to carry the name Stargazer) and one in particular caught my eye...
A Leif Ericson class USS Cerritos was answering a distress call from Earth (in a manner not dissimilar to the Enterprise-E in First Contact), but before the Cerritos could reach Earth a Klingon Bird of Prey manned by Captain Kirk beat them to it.
But an unforeseen consequence of Kirk's time hopping erased the Leif Ericson class from reality.
It was a short blurb, but I actually felt chills. I'm reminded of the scene where Spock expresses uncertainty on how to accurately bring them back to the present, and Bones tells Spock to just go with his gut or something along those terms.
With the implied context that a miscalculation on Spock's part led to the erasure of the Leif Ericson class and presumably all hands, do you think Spock made the right call, given what he knew at the time?
But if it never existed at all…well, there’s literally nothing lost.
But from an objective, non-linear perspective, the USS Leif Ericson did exist, before it was erased. A temporal agent with a timeline map would be able to follow the ship across its own personal timeline, until the point where it abruptly ends because the timeline it is currently in caused it to be erased.
It's similar to the Federation and billions of Borg lives existing and not existing in First Contact, or any of the myriad times the Federation was erased by time travel, and then restored.
Spock just rolls with time travel ever since he went back, pretended he was his distant cousin, and saved his childhood self from venomous space wolves or whatever that was.