In some sense, they did. The world may not be full of human-like robots autonomously roaming the wastelands^Wurban landscape - but it's chock-full of actuators,

In some sense, they did. The world may not be full of human-like robots autonomously roaming the wastelands^Wurban landscape - but it's chock-full of actuators, sensors and batteries. There are sensors and actuators in your coffee maker. There are plenty of them in your car too, whether they control the wheels, or the angle of the mirrors, or the height of the windows, or the state of your door knob. Etc. And all of those robotic parts were mostly made by... larger robots in factories.