[somenameforme]

It extrapolates broadly. It's kind of a funny thing. When somebody doesn't know much about something but wants to pretend they do, their vocabulary comes off sounding like a thesaurus of vernacular, but when you speak to somebody who genuinely knows something, to the point of having an intuitive feeling/understanding of it, they could easily explain, at least roughly, even the most esoteric topic in a relatable enough language that a high schooler could understand.

Space stuff is another domain that's just chock full of this.

[watwut]

I don't think this is true. Knowing something well and being able to explain it in simple terms are unrelated skills. Plenty of people who know their domain super well just can't explain to lay person.

[vacuity]

You're right. Recently there was a thread about how some (many?) people know a field well but can't teach well, and some people know and teach well.