I'll tell you why this time is different. Each time we had growth in technology that had the potential to displace a huge number of workers that technology also enabled a massive decrease in the costs of transactions (railroads, motor vehicles, the internet, etc). This allowed a massive growth in the economy which enabled these displaced workers to find new jobs. Also consider that the growth in technology didn't eliminate jobs, but it shifted them. The technology of old still required a mostly proportional human energy input to produce output. New technology decreased that proportion, but it didn't eliminate it.

This last point is the difference that this new wave of automation has compared to the waves of past. It is unprecedented in human history to be facing a future where human effort can be multiplied by such enormous multiples that the value of labor approaches zero. This coming automation revolution would have to simultaneously grow the economy to greater proportions that automation reduces the cost of labor. I don't believe this will ever be possible, but definitely not in the time period that a properly developed AI and robotic technology could corner the market in labor (once developed, less than a decade). Society is not prepared for what is coming, and it will be disastrous.