A properly-run academic department insulates its students as completely as possible from politics. If, as a student, you're having to concern yourself with departmental politics, it's a sign that your advisor isn't doing their job.
That said, while your advisor's job is in part to protect you from whatever politics are going on in your department, it is important that you not be completely politically naïve when you finish.
So your advisor probably shouldn't try to keep you totally in the dark if there are political shenanigans going on in your department or university... but they should do what it takes to ensure that those shenanigans are "not your problem." In other words, said shenanigans should be educational (possibly even entertaining), but not distracting, stressful, or have any other impact on your primary purpose in life: getting your dissertation out the door.
