>Maybe on paper. But the snappy low-latency feel of TUI apps in the terminal is a joy, and unequaled in GUIs.

This is not true at all. Terminal emulators are GUIs, the TUI is just another layer on top of that GUI. Using a TUI will always introduces additional latency, depending on the quality of the terminal emulator.

I do not know what GUIs or TUIs you are using, but my KDE Apps are all extremely snappy.