Yeah, welcome to 1980, where a library coming from a roguelike shaped almost all the TUI's for Unix until ~2010 or so, Curses.

A 386 could run NetHack at blazing fast speeds and read the news in a TTY perfectly well.

A multicore machine can't get the basic thanks to the 'wonderful' JS. Heck, even s9 Scheme from http://t3x.org ships a Curses module, enough to drive some text and maybe boxes/menues and it should fit in two floppies. A single one if the image it's generated later on-disk.