Indeed - in apps like CS6 - where the content is created primarily via the tools, they're shown for quick access, but made less prominent in order not to distract from what's being produced.
In Word, however the content is primary created with the keyboard. So removing tools becomes more of a possibility.
Bold Ctrl+B, Italics Ctrl+I, Underline Ctrl+U. Want to save? Ctrl+S. Want to print? Ctrl+P. Indent? Tab. Left, Center, Right-align? Ctrl+L, Ctrl+E, Ctrl+R. Increase/Decrease font size? Ctrl+>, Ctrl+<.
You don't need to use the toolbar at all for common operations.
Word's problem is that it has evolved so many features that there is NO reasonable interface to access them. I have been using Word for two decades and still I find myself resorting to features like the Format Painter because I cannot find the settings to fix a run of text.
Having a big GUI that looks like NASA mission control made an application look like value for money.
Now most people have more features in their software than they need and with apple leading the way in simplicity and usability a sleek interface is much more marketable.