The law of accelerating returns is made by picking a high recent point and a close to zero starting point, extrapolating in between, ignoring any low points or decreasing endpoints, dishonestly claiming prediction hits (see his recent accounting), and finally, reusing the same cherry-picked datapoints.
It's not a counter-argument.
In this essay I argue the following:
Full essay: http://www.gwern.net/Slowing%20Moore%27s%20Law