Again: Is that still Spock though? Imagine Krypton never exploded, and Kal-El as Superman instead came to Earth as an evil conquerer, murdering the world leaders and becoming a dictator to the whole planet.
Would that still be Superman "just we are seeing him take on different challenges"??
No. "Superman" is the amalgamation of Kal son of Jor-El and Clark Kent. In your hypothetical, he was never Clark Kent.
But here is where the fallacy creeps in.
First you equate the individual to a state of being. They are not the same. More importantly, however, there is a huge range or variance where the two intersect. And from a creative standpoint, there are invite combinations, all viable for a storyteller to use. As such, if a DC writer chose to tell your story, he'd be perfectly in his right to do so. Likewise with Spock.
Except that's not what happened here.
A more appropriate comparison would be Kal gets to Earth, but, when he's still a baby, the Old Ford falls on Glenn Ford during a tornado while he's on the phone being blackmailed by Lionel Luther and keels over. So Clark grows up with only Martha's influence. In the end, he's probably mostly the same do-gooder, but there's certainly to be some effect on his personality and daily life--his relationship with Lois, for example.
That's nuSpock in a nutshell. He's still the half Vulcan/Human Science/Executive Officer of the Enterprise, but the inner bits are scrambled up a bit.
