IMO this extremely, extraordinarily true. And in my experience, it's somehow even more true for disagreements among scientists. Even though every scientific field is, in some sense, about defining a shared set of extremely precise jargon. (I recall two very well-respected scientists screaming at each other about the definition of "acidity" for instance)
It's frustrating because when trying to engage in intellectually curious dialog on HN sometimes people will attack my character and get upset because our perspectives seem to differ on the meaning of a specific word. When trying to reconcile the meaning sometimes people get upset and dismiss it as "that's just semantics". Semantics is the meaning of words... If our disagreement stems from differing opinions on what the word means how else can we reconcile or discuss the topic constructively?
The last time this happened I think the crux of the debate was the meaning of "unconstrained capitalism". Pretty sure the other person and I agreed on everything (values wise) except the precise meaning of that term, and the misunderstanding led them to accuse me of being unsavory.
These exchanges tend to discourage me from engaging in HN for a while.