In the 90s, the relevant user-facing OSes for computers were MacOS and Windows. There were at least real, meaningful attempts at competition in the consumer sp

In the 90s, the relevant user-facing OSes for computers were MacOS and Windows. There were at least real, meaningful attempts at competition in the consumer space with, most notably, OS/2 and BeOS. (OS/2 is seen as a commercial failure these days but quite a lot of people ran it.) MS-DOS from Microsoft was also competing with IBM PC DOS and Digital Research/Novell DR-DOS. In the early 90s, Atari TOS, RISC OS and AmigaOS were not completely down for the count yet. In the UNIX workstation market you still had SGI IRIX, Solaris, HP/UX, and more. Now, looking even in that space -- well, maybe there's a Linux box or two, but more likely you're going to find even more macOS and Windows.