Maybe where you live, but in America it has a good connotation - it’s a good thing to be shrewd.
I really think it depends on which part of America you're referencing. Yes, shrewd can be a positive attribute. However, it can also have pretty negative connotations. Honestly, shrewdness in someone climbing the corporate ladder could be seen as a good thing. But, when I see the word shrewd, my first reaction is that the person must be calculating, self-important, and a real b****. I guess it's sort of along the same lines as describing someone as "tough and no-nonsense." Yes, in some areas those could be seen as positive attributes but in a lot of areas they're seen as more polite ways to describe someone who really needs to come down off their high horse and realize that the world doesn't revolve around them.