@ArneBab The problem is that only unified things are inside emacs, but all other programs either rarely emulate emacs behavior or (what is more usual) have ad-hoc not consistent solutions. Solutions for completion, candidate navigation, window/pane management, tabs and a few (or many) other things. IMO all those tools should be implemented on the level above the emacs and be composable so all the apps can benefit from it.
@abcdw Do you know emacsy? (was it you who wrote it?) https://www.nongnu.org/emacsy/manual/emacsy.html#The-Garden