Comment by Findecanor

Today I agree that it would make much sense for LoongSon to jump on the RISC-V bandwagon.

However, designing a CPU takes years. Back when they transitioned from MIPS to LoongArch, RISC-V wasn't mature enough to have all the functionality that their MIPS cores did. There was no ratified Bitmanip extension and it was unclear what kind of vector extension that it would get.