I guess you weren't there. We did em-dashes on typewriters. We just turned the platen knob down one click, typed _, and turned it back.
I'm a self-taught typist, with all the quirks that comes with (can type programming stuff very accurately at a 100+ WPM; can type normal stuff at a high WPM as well, but the error rate goes up).
Moreover, your home is not representative of the millions of typewriters in businesses around the world.