I just met someone a couple of days ago who has active Q clearance. He's a friend of a friend. What I learned from him is that a lot of people have it, but using it is based on need-to-know restrictions. Your access to files must remain compartmentalized. You can't just go searching the archives without having a reason related to your current project. You'll be questioned.

I think what was special about Q was that Trump removed his need-to-know restrictions, so he could search the DOE archives freely.