I specified "popular 64 bit ISA", which comes down to amd64 and arm64. But you can include Elbrus and LoongArch if you want. Or POWER. Or Itanium.

> I assembly by hand almost any function that is not too simple I can make it shorter on Cortex-M33 than on RISC-V

Not if you use the RISC-V ISA properly.