Thing is, many of those niche companies are single-founder businesses, where founders do not want to hire employees. Many reasons, not necessarily financial: in my case, I just got tired of dealing with people and their issues and decided I want to depend only on myself.
So, jobs of this kind are rather scarce.
Also, in a tiny business, the founder will usually be super-efficient and productive. Most employees are not. There is an impedance mismatch: a hired programmer will talk about the latest and greatest JavaScript framework and the need to rewrite everything in YaddaOfYadda, because that's what the World is doing these days, while the founder will think about the benefit for the users (usually none) and the immense costs (in terms of money, bugs, and time wasted).
Because of all this, it's not very probable that you'll find a job at a niche company like this.
It doesn't have to be as tiny as in the article, but more just a small, bootstrapped company with a good niche to serve. These sorts of company should be very common and jobs at them should be plentiful (due to number of shops, even though each would be small), yet they are nearly impossible to find. I bet they have an equally poor time of finding people. Seems like an under served market.
So, jobs of this kind are rather scarce.
Also, in a tiny business, the founder will usually be super-efficient and productive. Most employees are not. There is an impedance mismatch: a hired programmer will talk about the latest and greatest JavaScript framework and the need to rewrite everything in YaddaOfYadda, because that's what the World is doing these days, while the founder will think about the benefit for the users (usually none) and the immense costs (in terms of money, bugs, and time wasted).
Because of all this, it's not very probable that you'll find a job at a niche company like this.