And who would down vote me, I wonder, other than a "club" member. All professions are clubs, with jargon, private societies/associations with barriers of entry

And who would down vote me, I wonder, other than a "club" member. All professions are clubs, with jargon, private societies/associations with barriers of entry, apprenticeships in various guises to screen out the unwanted and unworthy (and identify real talent early and nurture it), an internal network at various levels, the means to oust the rogue elements, the list goes on. In London there were called the guilds, going back over 1000 years and still with substantial influence and power today. Some clubs exert more power and control over their role in the wider world than others. Lawyers and doctors are two that come to mind as deeply protective of their club, for reasons potentially both virtuous and not. I felt I was just stating the obvious.