Yes, noise control and privacy, but if you don't want it, feel free to get rid of it. It'll feel more open, and having a door in this location is rather rare so it won't be odd not to have one.

Keep the doorframe and the door for a while in case you change your mind. There may be a reason you need that door that is not obvious. Beside privacy and noise, I wonder about the heat and air units in your home. I would live in the house for at least one year before I would get rid of that door. Unless you are planning on changing all of the doors, trying to find a match later would be a nightmare.