The only skills gap bigger than the one for programmers is the one for statisticians.
The whole web industry is accumulating vast quantities of data and storing it, magpie-like, as if it has intrinsic value, aided by ever-falling prices for storage. But the data isn't valuable. It doesn't mean anything until somebody who knows what they're doing looks at it, sifts through it, and produces a tool that lets others use it to draw valid and useful conclusions.
But hardly anybody does this. Instead we apply the most absurdly basic analyses and build whole businesses around them. We are messing around in the shallows, while the ocean of data gets bigger every day.
If you want to find yourself enormously over-employed for the next decade, learn a bunch of statistics. As a bonus, find a way to fit machine learning in there, but we even have way more people who understand machine learning than understand what it is we should be teaching them.