People are going to come on here and claim that the article was talking about desktop computing. However, backend computing is a much larger market, and is much more varied, with Windows actually having a smaller share.
When I graduated from High School (1964) There were no computers in the school. A offsite mainframe with punch cards was used for administrative work. Even as an EE student in college (RPI 1964-68), There were no computer related courses required. After graduation, I started working as an engineer and ended up teaching myself about computer hardware and how to write programs in order to design the new products the company desired.