Maybe, but if you don’t have a crew, besides having a much lower profile, the tank can become more or less disposable— if it’s really a drone, you don’t need the heavy armor, you can just make more (and much cheaper and lighter) tanks.
I think most people greatly underestimate how difficult it is to traverse terrain in a tank. You are constantly avoiding obstacles...usually holes in the ground. We already have heavily armed remote controlled weapons (predator drones). So I don’t think we will field unmanned tanks anytime soon.