I very intentionally did not write anything about finding engineers who are just good at the things you care about and not at other stuff, because every bit of data I have says there is a considerable component of general engineering skill underlying most eng roles. No, it isn't totally one dimensional, but (in a principal-component-analysis sense) it is fairly low-dimensional.

There really are just better and worse engineers in the sense that eng A is better than eng B for virtually every job. But that's precisely why recognizing the competitiveness of hiring is important - the more you insist on narrowing your pool, especially in ways others also narrow theirs, the less likely you are to find the rare unknown great engineer.