About 8 years ago, someone on the job analysis listserv asked the question "What are the top 10 competencies needed for future jobs?" (or something like that). Without even batting an eyelash, I replied immediately "explanatory skill".
Explanatory skill is NOT the same thing as communication kills, and therein lies some of the problem. I can engage you, and maintain your interest, and you can still leave the room wondering what the hell I was talking about, or completely unable to convey the message to a third party. That may be good "communication" but lousy explanation. When I used to teach university, I would regularly ask my students if any of them had ever received explicit training in how to explain things well; the answer was always 'no'.
In a world that increasingly demands coordination amongst many stakeholders, often many disparate stakeholders with different levels of background knowledge or different personal investments in whatever the activity is, the capacity to explain so that people not only "get it", but accept it, and are able to serve as your proxy/avatar by explaining it to others.....well you can't put a price on that.
And that's not just a requisite competency for your middle manager. It is a requirement for being an effective lawyer, car mechanic, plumber, teacher, call center rep, sales staff, parent, spouse, neighbour, etc.
Of course, it almost goes without saying that when ideas or initiatives are very poorly thought out, explaining them clearly can often expose their weaknesses in ways the explainer did not intend. In such circumstances, a good explanation may reduce buy-in rather than the desired opposite.