I ran my last desktop computer (Sempron 2400+, ATI9200SE graphics card, 2GB ram) when I bought it with Windows XP, entirely on FOSS, with OOo, GIMP, Firefox, Thunderbird, and many other applications I can't now remember, and apart from XP which came with the machine, never bought any software. So yes, I agree with you about the applications having in some situations won the battle for supremacy.
I tried Ubuntu 5.10 way back whenever, and from that time only ever booted to Windows to update AVG Virus checker and ZoneAlarm firewall, so eventually it became obvious to me that WinXP was superfluous to my needs; all the apps I used were already on my Ubuntu by default or easily available. About two years ago it went from my machine and I ran Ubuntu 10.04 exclusively. After all those years of Ubuntu it never occurred to me that the Linux experience was anything other than user friendly; when I had to use Windows I always found it to be much less user friendly than the Ubuntu I knew so well.
My point is simply that user friendliness is much more down to what you know than any subjective judgment of an OS by someone who does not know it well, nor know how to use it.
I now know Ubuntu (actually Xubuntu 12.04) extremely well, but have no idea at all how to deal with Windows versions after XP. I'm sure I could do basic activities reasonably easily, but if I had to do anything complicated I would find it much more difficult than in Xubuntu
Xubuntu 12.04 user, and loving it!