I personally don't buy this argument. It's the same argument that a writing code in a higher level language. Once we have this HLL we don't need as many programmers because the language does all the heavy lifting. But what we've seen is a shift into different kinds of work. People adapt and get different skills.
But coder output is definitely higher now than ten years ago. And a lot of the work that's out there is of a much lower level of complexity, so the experts now are either working on things which need the requisite knowledge or working in places where their productivity is correctly compensated.
The thing is that a few years ago people were willing to pay designers to make Photoshop templates and that's it. Nowadays this simply won't do, so the work is moving up in complexity and the bottom tier is being handled by people with no specific training.
Finally, just because the work has shifted one way in coding jobs doesn't mean it will work that way in design. It is quite possible that the intermediate knowledge gap being created by better tools and more complex work just won't require people in that area, so we'll have both more experts and more newbies.
