It goes with the value of people competences as with the
value of information:
the rarer, the more valuable.
The history is full of cases like this of the printing workers
after Gutenberg, or of telegraphists during the XIXth century. These
competences do not nowadays justify any permanent advantages any more,
but they have justified temporary ones in the past.
A case boundary is whether the competences are or not shared by the management. Roughly, with stable technologies, at least part of the managers have grown from the workmanship and do have a real understanding of what their employees do.
Managers will have to iron some specificities away do deal with people. The point is however whether this abstraction process is a posteriori, i.e. abstraction of some known information, or a priori. In the latter case, the only reasoning left is based upon analogy. This situation is a weak one, especially in a context of competition.
On the project-product axis, both extremes tend to abstract away any concern for the specificities of the problems at hand, and thus of the competences of the people.