The reason SGI failed, and eventually Sun too, isn't because the world "chose wrong", but because their performance simply did not keep up with x86.

When these RISC-based workstations were initially released their performance, especially at graphics, was well beyond what a PC could do, and justified their high prices. A "workstation" was in a class by itself, and helped establish the RISC mystique.

However, eventually Intel caught up with the performance, at a lower price, and that was pretty much the end. Sun lived on for a while based on their OS and software ecosystem, but eventually that was not enough especially with the advent of Linux, GCC, etc, as a free alternative.