Although I don't disagree, the difference was that Microsoft had a monopoly on computing. Not just on PC but take computing as a whole and microsoft was hugely dominant. From a legal standpoint there is a huge difference.
Desktop computing -- in the 90s in the server area there was more competition, primarily from Netware.
It wasn't until the end of the 90s when macs started making an impression on peoples desktops, with the imac, but oddly enough if https://en.wikipedia.org/wiki/Usage_share_of_desktop_operati... is to be believed, windows still has a 95% share of the desktop/laptop market.
I believe it because Windows comes on all kinds of devices and supports all kinds of hardware mixes and SKUs. It effectively encompasses the entire price range in a way that Apple doesn't care to.
