What the headlined article is talking about is not a TUI-GUI split. It is talking about a command-line interface versus other forms of TUIs. As mentioned else

What the headlined article is talking about is not a TUI-GUI split. It is talking about a command-line interface versus other forms of TUIs. As mentioned elsewhere in this discussion, there were plenty of ways of end users interacting with MS/PC/DR-DOS without having to use the command-line.