I think what these articles lack is that being a good PM is more about the process vs. what one knows. A good cook, for instance, would generally have intrinsic knowledge about flavors, cuisines, preparation, plating etc. The more the cook knows about these areas the better she is and would command respect. PMing, on the other hand, has very little to do with the domain of the area you are working on. It is more about the process you use to figure out the following - building out a long term strategy for the area you are working on, breaking down the strategy into smaller parts and prioritizing those, working with and convincing your eng, xfn & leadership team that what you have going is the right thing, being very data driven to figure out what is working and doubling down on it, focussing on a market which is large enough but where you are differentiated etc.

I am not saying a cook or military person can't do that but I would be cautious to generalize.