My only encounter with the mythical COBOL Legacy Architect was at one job where we indadvertedly shared a desk. Since he was only in the office about 2 hours a months, others had assumed it was an empty cube and put me there. The rest of the time, he was making consulting bank in his mountain cabin. I think other than myself and the CIO, maybe 3 people knew who the guy was.
The flipside is that probably 90% of mainframe programmers were washed out of the industry in the mid-1990s. I remember seeing tons of useless resumes full of RPG and JCL and no C++/Oracle/Java/WinNT or whatever was hot back then.