Which observation? That the COBOL-type programmers (and we can add in RPG, and other non-sexy languages as well) are isolated from the rest of the industry? Sure. But in-house developers of serious, back-end-heavy apps have always been isolated-- including from each other.
I think if you started calling around to banks, hospitals, transport companies, oil companies, old-school manufacturing facilities, etc., and started inquiring about their existing codebases, you'd get a whole other set of anecdotes.
Which observation? That the COBOL-type programmers (and we can add in RPG, and other non-sexy languages as well) are isolated from the rest of the industry? Sure. But in-house developers of serious, back-end-heavy apps have always been isolated-- including from each other.