Design needs to have substance. 

Design as a result of copying design from others has no substance. And here is why.

Substance comes from design method (a way of designing) that gives relation to one who experience it and its subject that design is informing. Meaning, reality, philosophical truth that a design wants you to experience. 

By replicating design, only the appearance is usually copied, method and the underlying procedure are not copied. 

Even if you can copy the way of designing, the one who does it is different. 

You can print two toys that look exactly the same in a factory. But the manufacturing time stamped on each toy is still different. 

If you managed to print both toys at the same time, their coordinate and positions of the point in space are still different.