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Japan tried to build an operating system for the entire world, then the US government intervened
(www.xda-developers.com)
This is a most excellent place for technology news and articles.
There also were more than two PC platforms (and we barely have two now; Apple was pretty close to going away too). I miss being the Atari ST guy in a circle of people who all had different types of computers. It didn’t last very long but it was way more fun.