A changing means of production will likely shift the wealth from a previous ownership class to another. Whether that diffuses into the middle class is mostly a political problem. However the stronger a middle class is, (through access to capital) the faster technology production and adoption will become.

Or so is a school of thought of contemporary political economy (read Why Nations Fail by Daron Acemoglu. et. al. )

Example: the cotton gin did not make for a healthier middle class, since the political apparatus barred access to capital (and human rights and civic participation) for so much of the population.