It took me many years to learn that speaking in honest, innocent truths is not all there is to communication. Even if what you say is topical and meaningful, the way it is perceived by recipients has little correlation with how truthful your message is. This is what is meant when "factual information" is only one of four aspects of communication: https://en.wikipedia.org/wiki/Four-sides_model (see in particular the example at the bottom of the page).
Essentially, the best way to communicate something always depends on the receiver.
My approach has thus been to try and run everything I want to say through a "if I were the other party and heard this, what would my reaction be? Is that reaction what I'm trying to achieve?" filter. I understood the article as this being the "manipulative" element that the author wanted to eliminate. But for me personally it's been life-saving to have some way of making sure that I'm not completely misunderstood. And that will happen if you present the right information at the wrong time, in the wrong context, to the wrong people or with the wrong presentation. Yes, I deliberate a lot over how I word my emails...
This take on "communication is not just truths yelled into the void" is also reflected in several XKCDs: https://xkcd.com/1028/ https://xkcd.com/1984/ https://xkcd.com/1860/
And this one in particular is very poignant: https://xkcd.com/1576/