Working out the engineering challenges will probably take a decade extra, but I wouldn't listen to the ML researchers' opinions on this issue; the evidence that they are in the drivers seat is shaky. We're still seeing exponential gains in processing power and we're closing in on order-of-magnitude amounts of processing power being available in silicone as in a human brain. There is a pretty decent chance that there is some magic threshold around there where all these tasks become easy with current algorithms.