The jump to 80-column video displays was due to late 1960s CRT-based computers for data entry such as Four Phase and Viatron, which allowed people to enter punc

The jump to 80-column video displays was due to late 1960s CRT-based computers for data entry such as Four Phase and Viatron, which allowed people to enter punched card data on a screen and edit it. These of course had 80-column input. These were followed by more general purpose video displays like the VT50, which also had 80 columns for compatibility with punched card systems. This led to terminal emulator windows such as xterm using 80 columns. It is a clear historical path. (I don't know why you're bringing the Apple II into this.)