A: It started up with a Utopia - freedom of choice.
Windows powers around 90% of the desktops worldwide. It doesn't offer much choice. And the little choice it offers is limited to a few application software. For more than 15 years we have just two GUI for Windows - Luna (Pre-Vista) and Aero (Post-Vista). Ask average Windows users about the desktop environment they use. 99% of time you will get a shock response - they have no idea. Or at best the answer will be "Windows". They have just one word "Windows" for the OS, for the desktop environment and everything else. What does it mean?
- people are not so fond of software, they just want to get their job done using some software (often reluctantly), crying "choice" aloud just frightens them
- they don't worry about the source code and the RMS freedom associated with it
That's precisely why after so much trumpeting of the advantages of FOSS it's struggling to register in the mindshare of the masses. The often said "Resistance to change" is not the only reason holding the opensource platforms back. It's the lack of standards, simplicity, coherence and good applications, plus the ever growing chaos in terms of fragmentation and multiplicity in every possible form.
You need to clean the clutter by dumping 90% of the stuff that make up for freedom of choice. Then you need a benevolent dictator who can apply an adamant standard and QC system to really push FOSS on the Linux desktop forward, but then it won't be FOSS anymore.