> If we had a cross-platform usable GUI framework
I could swear there once was a (n)curses or otherwise text based GTK+ implementation / backend. It didn't do everything of course, and this was, I don't know, about 2003-2007, but you could compile a GTK application and run it in the console.
I tried finding a link, but unfortunately could not, can't even remember the name, I only remember building a piece of software that way that did GUI or TUI depending on how it was linked.
Could you be thinking of libyui, but it was QT and ncurses based. I think it came from SuSE with YaST.
https://github.com/libyui/libyui
https://yast.opensuse.org/