First of all, its obvious that the world wouldn't collapse in
this case. Yes, there are plenty of software, either home and
business dedicated, that relies 100% on Windows. Microsoft has a
large market around its operating system, a market commonly driven
by "sell plenty and earn even more" attitude. Such a single-crop
area.
"But life always would find some way. Something would have to
happen - so let's look at the possibilities, shall we?
"Would diversity work ?
Not so long ago, a home computer was usually 8 bit machine,
followed by 16 bit over time. I mean such traditional "consoles"
like Atari, ZX Spectrum, Commodore/Amiga, and so on. Software
developers, releasing a new game for instance, would prepare
different versions for different hardware platforms. So it was
possible back then! Well, actually, it still is - just look at game
consoles like PlayStation, GameCube, DreamCast and so on - it is
often possible for a game to be released for different platforms.
Of course, not always and not all titles, but it happens."