You still can use Windows with only a keyboard. Until very recently, MS was very good about maintaining UI consistency and having plenty of redundancy - simply holding down the alt key in Win7, for example, will display the keyboard shortcuts for all of the functions in the current window by underlining the relevant letter, in the manner that used to be displayed at all times in earlier windows versions.
Having recently switched to Linux, I've been astonished that some X applications seem to require the use of a mouse, and that many graphical environments don't have default keyboard shortcuts assigned to certain tasks. At least it's much easier to create and redefine shortcuts, and you can always open a terminal and type in the full commands as needed.
This is one of the things that's very annoying about applications that hide the menubar or lack a menubar entirely. Cycling through menubar options with a keyboard is far, far more efficient than attempting to use a keyboard with many of the poorly-thought-out experimental UIs that seem to be increasingly prevalent.
That daft "show shortcut letters when I press Alt" can be turned off so that Windows ALWAYS shows those underlined letters. Thank goodness. It is unusable else.
I would agree that X / Linux applications fail in this respect.
Also, Mac OSX by default will only tab between certain UI elements, and the option to force it to tab between all UI elements cannot be reached with the keyboard only, meaning if you start up without a mouse you can't turn on the relevant option to use it with a keyboard, with a keyboard...........
Having recently switched to Linux, I've been astonished that some X applications seem to require the use of a mouse, and that many graphical environments don't have default keyboard shortcuts assigned to certain tasks. At least it's much easier to create and redefine shortcuts, and you can always open a terminal and type in the full commands as needed.
This is one of the things that's very annoying about applications that hide the menubar or lack a menubar entirely. Cycling through menubar options with a keyboard is far, far more efficient than attempting to use a keyboard with many of the poorly-thought-out experimental UIs that seem to be increasingly prevalent.