>what Microsoft did was a major change with many, many thousands of man-hours invested into it; and many of those hours were UI/UX research, usability studies, analysis for the data phoned home by Office; does any of this sound like your typical Open Source project work? :)
No, and that's a problem!
Tell me LibreOffice isn't a MASSIVE project with thousands of man-hours invested in developing its under-the-hood features. How about finally recognizing UX design as a vital part of that effort? Or rather, its biggest flaw?
It's not as esoteric as copying "ribbons" or "reinventing the GUI". How about having buttons where the text isn't sticking 1 pixel to the left, some proper spacing to group elements belonging together and boxes that are aligned at all angles, so your eyes don't get tired after 5 seconds of reading the captions? How about sending 3 people into a real-life office environment where LibreOffice is used for a week and make detailed notes and interviews on which features are used most, are most annoying to use or most desperately missed and then rearranging the hierarchy accordingly?
I see such a massive amount of goodwill and idealism in the open source community but as soon as it's facing mainstream users it fails to recognize UX as an integral part of providing a viable alternative to commercial products. Microsoft absolutely needs competition in the Office space, I swear at them nearly every day for doing the simplest things they manage to make complicated. They can be beat. But it's not via features, it's via interface design.