The day we get a truly good, native binding, resource efficient, cross platform UI framework, then I will agree wholeheartedly.
I love a GUI in many cases! But if I'm building something, I personally want it across Linux and MacOS at least (personal and work, respectively). TUI answers that problem quickly, easily, effectively, and efficiently.
I'm actually amazed that we have never gotten to a really good UI framework that is cross platform. I really just want something like SwiftUI that's truly cross platform, personally. There are a million arguments to say that we do have cross platform GUIs, but all of them lack in some major way.
"a really good UI framework that is cross platform."
Just curious re: the obvious example of "The Web" - do you consider it "not good" or "not really a cross-platform UI framework" as such?
Maybe you should re-examine your priors, because reality is sending you a lot of data that refutes them. If it were feasible to do this, I think it would be done by now. There are a lot of reasons it is very difficult, and while there may be no reason it is impossible, something can become practically impossible when you pile constraint after constraint on it.
One example - wxWidgets exist, and wxDart exist, but getting to something half as usable as Flutter from there is almost impossible. I defy you to even build a layout engine that works on all three platforms. After that, you still have to find answers for theming, spacing, responsive behavior, component composition, inspection/debugging, hot reload, accessibility conventions and on and on.