Oh, your post was reblogged by @scandinavianviking, I failed to see it was not written by him. My Norwegian analogies was hence a bit irrelevant, sorry by that.

Microsoft is not at all as dominant as it used to be - its dominance was mainly ended by technological innovation and sheer luck.

One major blow came already as the Internet became more popular among regular consumers than the Microsoft Network. I'm very happy that it ended up that way. The Internet could have been as irrelevant as Usenet or Fidonet today. The next major blow was when Windows for Mobile failed becoming popular and Android became popular.

Microsoft is still very dominant on their Office series, it's much aided by government contracts and public schools teaching pupils and students The Microsoft Way of doing things, but I doubt things would have been different in a world without governments.