As design moves away from Skeuomorph, I think that traditional icons need to go through an evolution that no longer ties their meaning to physical imagery. My generation and younger will no longer perform physical copy and paste functions, as defined by early graphic design. I agree icons need to illustrate the function that they represent. However, I think it is time that our understanding and associations evolve along with design and culture. Lose the scissors.
This is my representation of cut, copy, and paste.