The areas that you mention only have a high barrier to entry because there is no bulk job market in those areas, plus no one has yet decided to write a 'x for dummies' book in it for the exact very same reasons.
There are more websites written everyday than kernels.
Web development isn't particularly easy, but has been made easier because there is demand for it that way!!
Let say you have a markup language. The language implements every kernel feature known to mankind. Now all you need to do to get your very personalized kernel is specify the interplay of the features though the markup. Lets say such language also keeps updated with all latest developments in Kernel development field. Over time you see, even the most noob guy producing their own framework to do a range of kernel work.
Kernel development will look pretty much like producing a HTML page. And you will have a dummies book for it.
This is kernel development would look if there were millions of jobs worldwide for it.
You could apply the same analogy for anything.
That makes me wonder what kind of technical skills have long lifetimes, valuable in the real world (as opposed to merely being technically interesting), and are difficult enough to acquire that one doesn't have to worry about competition against a low-paid worker army....
I read that article, and while i don't fully agree with it, there seems to be at least a grain of truth in there. He talks about how VB programmers are no longer wanted because VB.net is hot stuff now (the article was written in 2007.) He also talks about how one's professional knowledge counts for lesser and lesser as a programmer, and how a lack of any barrier to entry has resulted in a field flooded with cheap workers with no job security or general social prestige.
I consoled myself thinking this won't apply to the more sophisticated programmer, who is well trained in algorithmic and mathematical thinking. For example, writing machine learning systems, advanced statistical analysis or kernel development etc. DO have at least some barrier to entry, and these are not things that a random script kiddie can learn in a "x for dummies" book. Can a more senior engineer comment?