It's a hollywood movie though, of course they're going to hire a big name hollywood actor, that means most likely white, and thanks to the Marvel movies no one is more sought after than Scarlett Johansson, there's nothing wrong with that choice
The movie is going to be an absolute mess though, you got the director of Snow White and the Huntsman working with Dreamworks of to make a live action rendition of Ghost in the Shell, everything about that team up smells disaster, this is going to be one movie I'm going to keep tabs on just for the massive trainwreck that's incoming
They're likely going to cut back on some of the more "raunchy" parts of the work they're adapting as well, don't expect anything like the scene where Major Kusanagi wears her skintight flesh colored suite and tries to pull off the lid on a tank, muscles bulging and all, don't expect any subtlety as well, the preceding parts of the fight with the tank would be completely different, hollywood would demand dubstep action music in the background instead of the choir, and more explosions and gun fire instead of using quiet moments to create tension and juxtaposition
This is going to be bad, Shyamalan's Last Airbender bad, I don't think we want one of Hollywoods few female asian actors to be dragged down by this disaster, instead people should simply enjoy the original adaptation more, fans of Avatar: The Last Airbender learned that long ago