It's not clear to me how this relates to the question. Emacs and vim are native apps.
> In the most common case, both of these editors use the cross-platform "VT-100 UI Toolkit" (e.g. ansi escape codes in your terminal emulator), regardless of platform.
I daresay that the single most common way to deploy emacs is as an X11 editor, followed by a macOS editor, followed by a vt100 console editor. Emacs is a fully GUI programme, and has been for decades at this point.
I think that alone marks you as an unusual emacs user; the standard pattern for using emacs is to leave it running all the time (either in a window, or as a dæmon), not to launch new instances. But yes, it would be interesting to have numbers.
> Being useful in a terminal is a critical requirement for me.
Oh, certainly; in fact, I have 'vi' aliased to 'emacsclient -t' these days for just that reason. It's awesome to have a powerful, extensible editor available in the terminal.
I have EDITOR set to emacsclient (and some other aliases) and I find it far more convenient than an in-terminal editor, especially when combined with sudoedit.
I only use it for quick edits to files, when I don't want to turn my head from my terminal to my emacs window. Yeah, it's just a bit lazy …