The worst thing about the casting wasn't that they did it, if they just made her white and left it at that I could have lived with it (and actually, the rest of the cast was pretty good. I especially liked Batou in this). but then the movie turns her race into an inane plot point. Basically Scar-Jo used to be a japanese person but her memories were wiped by the villain and she was turned into scar-jo. It's like they were so embarrassed by this casting that they had to write excuses for it into the movie.
Everything to do with the villain is bullshit hollywood crap. Which is annoying cus they do have a good villain-like character in the film (basically taking on the role of The Puppetmaster from the 95 film combined with elements of the antagonist of 2nd season of the TV series), he should have been the only antagonist.
The movie also rings pretty hollow. They state a couple messages in the film but the film doesn't really have much to say about those messages. all the other iterations of GitS at least try to go much deeper with their themes, this one feels completely surface level.
The movie is surprisingly short though. I was expecting some bloated 2+ hour monstrosity (the GitS universe certainly has more than enough material for that) but it's a pretty neat hour 40. the movie moves pretty briskly and I didnt think it was boring. the parts when it was directly copying scenes from the 1995 movie were all pretty decent. So I wouldn't say it was a trainwreck of epic proportions. It was an awful adaptation, but it was also kinda breezy and forgettable.