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Although I've had an interest in computing that goes back a long way ( I was taught physics by a guy who had worked on the Manchester 'baby' as a post grad) I can only say that the credit in using Linux for everything goes to the countless people who have worked on the kernel, written the GNU tools and assembled the distros.
Installing a modern distro ( I use OpenSuse ) is simple - FAR easier than Windows - but of course not many users do that do they ?.
If 90% of Windows users are incapable of using Linux I'd say they were also incapable of using Windows - I don't see the difference in easy of use. OpenSuse installs with no fuss, a good selection of user programs and no user involvement other than ticking boxes, accepting defaults and choosing language.
I simply can't believe that people who otherwise wouldn't dream of having their choice restricted to one car, one supermarket, one smartphone or whatever will blindly accept 1 OS.
Back in the eighties all sorts and manner of people got involved with a wide, wide range of micros, wrote software, built hardware, became professionals and yet now 90% of Windows users can't cope with anything else - rubbish - and IF that's true then it's the monopoly of MS that has brought it about.