I know this is a "gotcha" comment, but it actually only adds to the author's point: language is fuzzy and imprecise. Moreso, that we assume it has far higher precision than it actually does.
We can think of communication as having 3 main components. 1) the intended concept being intended to convey. This is in the person's head. 2) The fuzzy compression mode (language) that is used to convey said thought. Be that words, writing, or interpretive dance. 3) The fuzzy decoder that turns the language into a thought in another being's head. This is filled with priors and assumptions that fill in many of the gaps.
The thing about this is that we usually learn to speak in pretty localized groups, meaning that our priors align and we have a lot of good faith (attempting to interpret intent rather than interpreting the words). But with a larger audience we have higher variance that makes what is obvious a priori a disastrous outcome. "Everybody knows" is not something everyone knows. https://xkcd.com/1053/