Yes. I agree with this.
Having command line and interactive terminal experience and actually programming your environment the more fundamental skill to have on mainframes.
I don't know -- It's been decades since I wrote any COBOL, and at the time I was pretty fresh out of a unix-centric undergrad environment. I was at home in emacs and the shell command line and familiar with unix utilities, but the mainframe was just another planet entirely. None of that experience really translated.
