It's a TUI if it uses text to build those elements.
You can be effective and powerful in any kind of interface, Just like you can be ineffective and weak in any kind of interface. People like TUIs because they're cool, and work over SSH.
It's a TUI if it uses text to build those elements.
No. All you've done is make a low-resolution GUI.
Yes. A TUI runs in a text session. A GUI runs in a graphics session. A terminal emulator emulates a text session in a graphics session - and allows you to run TUI/CLI tools. This is apparently controversial?