ARM64 and RISCV64 are so similar ISAs that whatever implementation you can do with one you can do with the other, given the same level of engineering skill and

ARM64 and RISCV64 are so similar ISAs that whatever implementation you can do with one you can do with the other, given the same level of engineering skill and effort. Apple probably spent billions to make M1. If someone made the same investment with RISC-V they could get the same results -- the main company currently pushing higher performance RISC-V (SiFive) has total funding of under $200m so they clearly don't have billions to spend. They've got an announced CPU (tested in FPGA) with ARM A72 level performance. That's only about five years of very incremental performance improvements behind (non-Apple) ARM.