What part did Gary Kidall failure to make a 16- bit version of his operating system play in it not being used

Answer 1

No part. Kildall's OS (CP/M) was the leading operating system of its time. It implemented a lot of innovative features, and supported some of the earliest personal computers. It ran on both Intel chips like the 8080 and the Zilog Z80. CP/M was well on their way to producing a 16bit version of CP/M for the Intel 8086 that was a full 16 bit cpu, when IBM entered the picture. IBM had decided to base their PC on the 8088 processor, which was basically the same as the 8086, only with an 8 bit bus, to save money on memory.

There are many stories about the fateful series of events that lead IBM to license DOS from Microsoft. Most have been discounted. One of the most likely stories is that Kildall was reticent to port CP/M to the 8088 because he saw it as a step backwards, and because the infamous "segmented" architecture that allowed the 16 bit cpu to work with 8bit memory, was a major pain in the butt for anyone who had to deal with it, as scores of assembly language programmers could attest for years to come..

IBM ended up licensing DOS from Microsoft, an OS Bill Gates managed to secure rights to after promising IBM they had a solution, which was at best a blatant ripoff of CP/M, and at worst, possibly a minorly tweaked version of a beta copy of CP/M for the 8086, depending on who you believe. IBM was concerned enough about the issue that the folded under pressure from Kildall over the legitimacy of DOS, and offered CP/M for the IBM PC, however Kildall's price was 4x that of DOS, and he ended up pricing himself out of the market.

Noone, including IBM had any idea that the PC would become the industry juggernaut it became, so it's hard to blame Kildall for his decisions. HIs ability to code an OS was never in question, and he went on to develope some groundbreaking seminal software in the subsequent years, including the first consumer interactive CD.

Answer 2

16 bit was used and for a long time...