Star Trek needed the recast and reboot more than Star Wars would, though. People will go and see a new Star Wars movie--which are always events--no matter what.
I've been mulling that very question, but I think Star Wars is more dependent on its big name characters than Star Trek, which has diversified beyond merely Kirk & Spock over the years. The average person could probably name some other characters like Picard, Data and Worf, but ask then for Star Wars characters beyond the ones in the movies, and you'll get a blank stare.
Remember, both franchises are in the same boat, they must appeal to a large, global, casual audience who has never read a tie in novel and has no idea about anything that hasn't been produced for movies or TV.
Envision two marketing campaigns. One says "Star Wars" and has a bunch of people nobody recognizes. The other says "Star Wars" and has a young blond guy with a lightsaber, a young brunette woman with cinnabuns and a guy wearing a gunslinger looking outfit. Which does a better job of grabbing the attention of the causal passerby?
And keep in mind the article I posted a bit above this one - Star Wars is not a slam dunk. It will have a lot of competition, some of it from Disney. The appetite for action-fantasy movies is large but not infinite.