Here's the bottom line:
It's a story. In the story, the writers have decided that the good guys are good, flaws and all, and the bad guys are bad, flaws and all.
The good guys win, after suffering a horrible loss (billions of Vulcan lives)....the bad guys lose (they all are rallied behind Nero, and what he says, goes). They die no less horrible a death than the billions of Vulcans whose lives they took....justice is done. The good guys save the day, the Earth survives, and the U.S.S. Enterprise continues boldly going forward....'cause they cannae find reverse!