Not a bad overview, although there are a few factual errors. For example, the article presents the development of the Macintosh as something which started in the wake of the failure of the Lisa in the market. This was not the case. There was actually considerable overlap in the development of the Lisa and the Macintosh.
Also, the article states, "NeXT solved this problem by basing its computer on Unix, the most reliable operating system that had ever been created." That sentence would be far more accurate if the word "desktop" were inserted in front of "operating system," as there are several server operating systems that are at least an order of magnitude more stable than any flavor of Unix, including IBM's VM and MVS systems, and Compaq's OpenVMS and NonStop NSK (originally from DIGITAL and Tandem respectively).