It's really a lot more than two markets. The high end communications systems that use MIPS have almost as high performance demands as a desktop or server. And currently the highest performance core is a POWER 9. But on the other hand you have a few places where x86 Atoms have made inroads as embedded cores, as in the UR robot arms I work with.
But really I think we really do overemphasize the importance of x86 because that's the architectures we have the most experience working with directly.
there's a really interesting market at the bottom as well - super low power CPUs. 8/16 bit stuff, not RISC at all (since DRAM itself is a huge power draw at that level), and so on. fun stuff.
But really I think we really do overemphasize the importance of x86 because that's the architectures we have the most experience working with directly.