As I, to some extent, resurrect things past, I have been murmuring & shouting ...
The heart of the human difference!
The heart of the "human difference"?
The human brain is about nine times bigger, on a body-size-adjusted basis, than that of mammals in general. Obviously, or so I think, the reason, therefore, is of interest. But let's take a step back first. Humans were a long, long way from the strongest of the species. So how did we win out over the Truly Big Beasties? Answer: Joining together in groups and outwitting and out-organizing the brutes. And how did that come about?
Or as British evolutionary psychologist Robin Dunbar put it, our brains expanded to store social information. (Relationship stuff!) To make a long, long story short, this "relationship stuff" allowed us to join together in bands, maximize what we now call "organizational effectiveness" ... and become Kings & Queens of the jungle and more.
My point here is to suggest that anyone, as so many do, who dismisses or diminishes "relationship stuff" and "communication stuff" as "the soft stuff" is not only a fool (per me), but also denying the essence of what it means to be human—and the reason we have ruled the planet, for better or for worse, for ever so many years.
(Source for most of this: No Two Alike: Human Nature and Human Individuality, by Judith Rich Harris.)