So is chess!

And chess was one on the first mental "jobs" to be successfully automated.  Just because something is mentally difficult doesn't mean it's immune to automation.

Why is programming so difficult and time consuming to learn? Because it requires memorizing a huge amount of very dry information, and very exact reasoning skills with a low rate of error. Those are exactly the kind of tasks that computers excel at and humans are terrible at. It is almost a miracle that the human mind can hammered into learning these tasks at all; exactness is not in our nature, we evolved to compute the world intuitively and in terms of rough estimates, not in black and white terms.   That is why good programmers, just like good chess players, are a rare commodity.  For now.

But imagine that 10-20 years from now the "exact" aspect of programming can be outsourced to a machine. Imagine if you could simply tell your computer "Write me a bug free function that does X" and it spits out the code in a matter of seconds.  Of course, programming doesn't just require "left brain" skills, it also requires intuition and creativity, especially for higher level stuff like design and requirements engineering. But anyone reasonably intelligent can now become an expert programmer in a matter of months instead of years.  



I am willing to bet that 90% of the work done by skilled programmers today, will be done by machines before 90% of work of janitors is done by machines.