Pilfering std::array all at once instead of element by element

When you have a vector and you assign the vector to another vector, elements are copied 1 by 1 and you get two identical copies.

When you move assign a vector to another vector, the entire internal array is pilfered at once. Elements are not moved 1 by 1.

When you move assign an std::array to another std::array elements are moved 1 by 1 to the new array.

Why std::array does not do what vector does, pilfer the entire internal array at once instead of moving elements 1 by 1?