However, the x86 architecture is rather poor in many areas (extremely low register count for example)
Sparc, Power, Alpha are all better architectures than x86 (or amd64), but since they can't run the software that can run on x86, and that software is a huge percentage of the industry, they are limited to the server niche.
the highest performing processors always have a large price premium attached to them. IBM makes really good profit margins on the Power line, but they do also include capabilities that are not found on x86 systems. These capabilities are usually not worth their cost, which is why it remains a niche, but if you need them, they are cheap at that price.
But the point was that just because they didn't jump on the latest bandwagon doesn't mean that they went bankrupt.