Conway's Law Is Real
goodroot.ca
goodroot.ca
I'm guessing the author has met people who think "soft = easy", and dismiss it like that.
"Soft vs Hard" isn't equivalent to "easy vs difficult", it's closer to "intuitive vs systematic". (I suspect soft skills are under-valued and under-appreciated because it's harder to fairly measure and evaluate non-systematic traits).
So of course communication is a "soft problem".