You have moved the discussion away from the original points. What started this is a sentence in the article encouraging readers to continue because the author will explain the concepts behind potentially new words. The poster I replied to complained about that sentence because it does not convey that the topic is complex.

But almost all important topics are complex, and all education has to start somewhere. My claim is that insisting we emphasize the complexity rather than assuring the understandability is gatekeeping because it discourages new entrants and promotes an aura of mystery around the subject.