Today I learned that Windows 3.0 supported the 8088. Why? For what reason would you want to run an OS on a CPU that was already 11 years old at its release? And at a time where (I heard) you had to upgrade every 6 months to stay relevant.
It is important to note that plain DOS did not play all that well with 80286 processors or better for a long time, and Windows 2 (which had somewhat solved that problem) had been a poor seller because Windows 2 sucked. The CPU speed was fine, but what most users cared about was RAM. Because DOS was never meant as more than a quick-and-dirty OS for the first 5150s, and was supposed to be replaced with something better, it is limited to the same 1024 MB of memory that an 8088 can address. Microsoft was able to maximize this by consolidating system functions with a trick of the processor, but this imposed a hard ceiling. This means that DOS is locked at 640K of memory without special tricks. The first workaround was EMS, debuting in 1985. This involved a dedicated ISA card with RAM on it, that used bank switching to trick the computer into thinking it was only using 640K. Hardware EMS (not the later emulated EMS that many people from the 90s are familiar with) was compatible with an 8088 because of this cludge, limiting the value of a processor upgrade. A later bank switching solution that just used ordinary RAM, called XMS, worked much better but required a 286. For many users, XMS was the first reason to upgrade from an 8088. From what I can determine, XMS was publicly released in 1988. Much later, applications just started throwing DOS out of the way and ran in what amounted to an entirely seperate OS. This is what the ubiquitous "DOS4GW PROTECTED MODE RUNTIME" message many classic games once ran on startup meant.
This is a long-winded attempt to explain that, for most users in the late 80s, buying a 286 or 386 meant shelling out an extra several hundred dollars for something that provided them with
no benefit whatsoever. The contemporary meme about constant updates was just that - a meme. Computers were incredibly expensive, and only the most obsessive people would replace perfectly good hardware with something that was often only a little better than what they had. You could still walk into a store in 1990 and buy a computer built around an 8088. There were huge numbers of workstations in active use that ran an 8088. Most importantly, the same setup that allowed Windows 3.0 to run on an 8088 also allowed it to run in Real Mode (the same 640K limited setup DOS uses) instead of the compatibility-breaking Protected Mode (which is what allows a 286 or later processor to access all your RAM without bank switching), giving it compatibility with a great deal of DOS software that would otherwise be unusable. This gave users, particularly businesses, an excellent bridge capability where they could use new software on their older machines and old software on their newer ones.