riscv is just an instruction set. in a lot of ways its not as nice as AArch64 or x64. I don't see a strong impediment to having a world-class riscv processor, but it hasn't happened yet and the only reason to pick riscv vs arm is that you're a bottom-feeder, don't want to pay arm licensing fees. People who will switch architectures to save a few cents aren't people who make or buy world-class cpus.