thought-provoking essay I highly recommend.
I agree that wealth disparity is a problem and it is getting worse. I'd like offer a hypothesis as to the cause. In the "golden quarter" U.S. citizens were #1 in both personal and economic freedom. I recently saw we have dropped to #20 in personal freedom (scroll down for link) and #16 in economic freedom. When people are not as free as they wish and when risk is not rewarded (covered in the essay) then there is very little chance new, and better, jobs and prosperity will be created.
As the essay states, "we were promised flying cars, instead we got 140 characters" (smartphones).
Read it and let me know what you think.