The difference there, in Debian's case at least, is that there is a distinction between the frontend and the configuration backend; you're probably most familiar with the `newt` frontend, but there's also `text` (for textual entry without using curses or anything), `noninteractive` (for just use the defaults), gnome, kde, teletype, or even 'web' which does not seem to work effectively but is a neat idea regardless.

TUIs which are just TUI views of data you can get otherwise are fine; TUIs which are the only way to interact with something... less so.

I like TUIs, but if given the choice between a TUI or a CLI program, I'd take the latter. You can always create your own interface from it. Better if it's backed by a library.