Not just price and speed. The original motivation behind RISC was to make a chip that was simple enough to fit all the functionality onto one die. However, chip

Not just price and speed. The original motivation behind RISC was to make a chip that was simple enough to fit all the functionality onto one die. However, chips have been on a single die for many years, so that's no longer an advantage. The actual instruction set design is much less (but still) important these days. There aren't many "pure" RISC designs left because the universal demand for accelerated encryption, decompression, vectorization etc outweigh the ideological need for a pure design. IMHO what's more relevant today is having an instruction set that compilers can fully exploit, rather than having an instruction set that's optimized for human understanding. In other words, it's no longer a decision between complex and simple.