No one really wants to hear this, but in the world of 16 bit architectures the 8086 was clean, straightforward, easy to code for, easy to optimize, and vastly cheaper than the minicomputers competing in the same space at only moderately higher performance levels. It wasn't until the mid-80's and the mess that was 286 protected mode[1] that people started to sour on it.

[1] They had a bunch of new transistors to spend, and could pick any two of "performance", "address stretch" and "memory protection". They did the MMU before the stretch, and paid dearly. The 68k made, in some sense, the opposite choice and had fewer growing pains in the late 80's. By 1990 no one cared anymore.