Why would Spock be so revered on Ni'Var if he was unsuccessful at saving the Romulan people from the destruction of their home planet? I could see him being admired by the Vulcan people (not necessarily for reunification, as it seems the government of Vulcan was not keen on that), but those Romulans who made it to Vulcan or its colonies would be refugees, I imagine, from the Romulan homeworld, maybe 10,000 like the Kelvin Vulcans who fled to New Vulcan (who had reasons to hate Spock, too, for leading Nero to their world).
Are we to assume that other Vulcans somehow were persuaded by Spock that reunification was necessary or desired? Or perhaps he had followers on Vulcan (his son? Saavik?) who persuaded them that this was a good thing?
Are we to assume that other Vulcans somehow were persuaded by Spock that reunification was necessary or desired? Or perhaps he had followers on Vulcan (his son? Saavik?) who persuaded them that this was a good thing?