Who is to say that L.C.A.R.S is not an advanced version of windows. Maybe Windows L.C.A.R.S.
Well MS might have a monopoly on the desktop - but in other areas other OS's have a fairer share, the tendency if anything is for MS's new efforts to fall on their ass recently, so there is no reason to believe they will continue in power into the 22nd century, let alone 24th.
The next twenty years will see a massive change in the way we use and interact with our PCs both in business and at home - whether MS can survive this is up for debate...