Among other things, terminal based programs support flexible remote workflows via ssh and tmux.

Edit: It's slightly off topic, but it might be easier to understand the draw of terminal based interactions in the context of a larger toolchain and workflow. So for example: ssh for remote access, tmux or Emacs for session management and program tiling, ranger or similar for file management, and Emacs or a Vim equivalent for text editing. Mainstream DVCS and build automation tools all provide full functionality via command line. A terminal based spreadsheet program is an obvious fit for such a toolchain.