When one tractor replaced ten* farm laborers in the 20th Century that was also the case of a machine replacing workers. Just because you still need one guy to drive the tractor doesn't change the fact that a net 9 laborers lost their jobs to a machine. It's exactly the same thing with modern robots, which also need to be built, programmed and repaired by human beings. Not to mention all the research that goes in developing new and better robots. Japan, which has more industrial robots than the rest of the world combined, has an unemployment rate of 4%. So how does that leave your theory? *I'm making up this number, obviously, but you get the point.