I think one of the main arguments in favor of RISC-V is the permissive licensing. A lot of the people moving to RISC-V are absolutely weighting this heavily in

I think one of the main arguments in favor of RISC-V is the permissive licensing. A lot of the people moving to RISC-V are absolutely weighting this heavily in their decisions. The RISC-V folks would probably tell you that the compressed instruction set nets the same code density benefits you'd see on more complex ISAs. Myself, I haven't studied it enough to have a real opinion. RISC proponents tout its benefits for energy efficiency, which is a pretty important thing these days. Though, that might be up for debate. This paper states that "there is nothing fundamentally more energy efficient in one ISA class or the other. The ISA being RISC or CISC seems irrelevant." <https://research.cs.wisc.edu/vertical/papers/2013/hpca13-isa-power-struggles.pdf https://research.cs.wisc.edu/vertical/papers/2013/hpca13-isa...> Personally, I think the RISC vs CISC debate is just a little bit dated. The ideas behind RISC were new and exciting in the 80s. The equation had changed and there was a lot of room for innovation and improvement with sweeping changes to computer architecture. They were thinking about how instructions could be pipelined, how compilers would allocate registers, how profiling showed that seldom-used instructions can be deadweight that literally holds a system back. Then in the 90s, the equation changed again. Pentium Pro style superscalar architecture showed that you can do well with even a terrible ISA if you're able to throw enough transistors at it.