The article is from December 1987, when nobody yet knew that it would end up that way. The Compaq Deskpro 386 had just been released in 1986 (thus unmooring the “IBM PC clones” from IBM), the September 1987 release of Windows/386 2.01 was only a couple of months ago (less if you account for print turnaround), and development of what would initially be called NT OS/2 would only start in 1988, with the first documents in the NT Design Workbook dated 1989. Even OS/2 1.1, the first GUI version, would only come out in October 1988 (on one hand, really late; on the other, how the hell did they release things so fast then?..).