Alderaan didn't have the familiarity of Vulcan - it was just the name-dropped place Leia grew up. Not that it's any less devastating to the character, it just didn't have a connection to the viewer.
I suppose they could have destroyed a new or less familiar planet that Spock's mother was visiting, and the loss of Amanda could still be a factor. But it's like poetry - it rhymes - Prime reality Romulus is gone, alternate reality Vulcan is gone, at opposite end's of their Spock's lifespans.
I suppose they could have destroyed a new or less familiar planet that Spock's mother was visiting, and the loss of Amanda could still be a factor. But it's like poetry - it rhymes - Prime reality Romulus is gone, alternate reality Vulcan is gone, at opposite end's of their Spock's lifespans.