Just before reading your very good article, I read Joan Didion's quote--I write to know what I think. Writing helps me to sort out my feelings, to give some context to various experiences, on occasion to amuse or entertain--or at least to try.
I understand the wisdom in the words, know your audience. From my perspective, I started writing on Medium for the reasons I describe above and had no thoughts or expectations about reaching an audience. In fact, I'd read on Medium not to expect anyone to even read what I wrote for at least the first year.
So, I just wrote and, in time, the audience found me.