A goal of research scientists is to create robots so effective at running matters that all of mankind in essence becomes akin to the upper class - waited on hand and foot. To be effective in these roles, robots would have to repair and reproduce themselves, or each other, i.e. propagate; be able to adapt to changing circumstances, i.e. learn; and, since mankind can't be bothered, make logical determinations, i.e. think. Standing between the robot and sentient life forms, then, lies only emotion - hopes, caring, desire, rage - the motivators. In pursuit of this dream servant, scientists are casting a jealous eye on biological elements, which can propagate, learn, and think. But biological elements invariably carry the capacity for emotions. Even the amoebae reacts to defend itself, to escape, and moves toward that which it desires.
Where is the line to be drawn? Do we, the Zetas, not use a massive computer for data storage and communication between alien groups in the Service-to-Other orientation, and does this computer not use biological components? We equate this to your use of wood and leather, as the biological elements we use are not alive. They cannot propagate, nor do they move to defend themselves or move toward that which they desire. They do not have desire. They are dead. This is the ethical guidelines we use in creating robots, but these are not simply guidelines we have determined among ourselves. The Council of Worlds, which oversees all situations where one intelligent life form can enslave another, forbids the use of living biological material as components of thinking machines. The robot that propagates, learns, thinks, and as all life has emotion is alive, yet enslaved, as controls would surely be put into place to prevent the servant class from arising. Thus, media scenarios such as The Stedford Wives, or The Terminator, or Star Trek's Data would not be allowed to develop, not even if scientists in 3rd Density managed to develop them, which is far from likely. That those in 3rd Density, who are emerging souls in the process of determining a spiritual orientation, would attempt to do so is one of the reasons for limiting the capabilities during 3rd Density.
Mankind, in short, is too dumb to create a handy-dandy version of intelligent, sentient life. One, per their desires, which would never break down or talk back, would always look good, be compliant in bed, foresee one's needs, repair the car, be infinitely loyal, smart as a whip but never look down on the master, and never suffer from neglect. The child's dream.