When I worked ar Sherwin Williams, I got good enough with the TUI that customers could rattle off their orders while I punch it into the computer in real time.
It's absolutely crazy that a well designed TUI is so much faster. It turns out that if you never change the UI and every menu item always has the same hotkey, navigating the software becomes muscle memory and your speed is only limited by how fast you can physically push the buttons.
The program had many menu options added and removed over the decades, but the crucial part is that the hotkeys and menu indexes never, ever changed. Once you learn that you can pop into a quick order menu with this specific sequence of five keys, you just automatically open the right menu the moment a customer walks up. No thought, just pure reflex.
UX absolutely peaked with TUIs several decades ago. No graphical interface I've ever seen comes even close to the raw utility and speed of these finely tuned TUIs. There is a very, very good reason that the oldest and wealthiest retail businesses still use this ancient software. It works, and it's staggeringly effective, and any conceivable replacement will only be worse. There simply is no effective way to improve it.
Edit: I will say that these systems take time and effort to learn. You have to commit these UI paths to memory, which isn't too hard, but in order to be maximally effective, you also have to memorize a lot of product metadata. But the key is that it really doesn't take longer than your ordinary training period to become minimally effective. After that, you just pick up the muscle memory as you go. It's pretty analogous to learning touch typing without trying. Your hands just learn where the keys are and after enough time your brain translates words into keystrokes without active thought.
It's a beautiful way to design maximally effective software. We've really lost something very important with the shift to GUI and the shunning of text mode.