Job security.
It’s why we have reminants of New Greek and New Latin among Doctors, Philosophers, Biologists, various Scientific Disciplines, etc.
Chemistry seems to have somewhat of a valid reason for precision… although its standards of nomenclature also show shifts and changes due to fads of the time.
Jargon is fine if it carries extra information. Sometimes a single word is better. But in my experience, there’s not much you couldn’t teach to a young child that adults learn about in _some_ form or another so that they can understand at least the ‘gist’ of the concept.
Yeah. Job security. If they don’t understand us, we keep our jobs longer.