Most systems I interface with are remote or headless. Forwarding X is annoying as fuck and to be avoided at all cost, so the more I can do though the terminal, the better.

PS: I'm also old enough to have been a regular user of Norton Commander, the application MC (Midnight Commander) is based on (inspired by).

EDIT: Norton Commander was a DOS app and so useful that it prompted Midnight Commander, one of the earliest applications developed for Linux. So MC kind of pre-dates Linux in a way.