That's not really how it works. There are only a few companies on the planet that are licensed to create their own cores that can run ARM instructions. This is an artificial constraint, though and at present China is (as far as I know) cut off from those licenses. Everyone else that makes ARM chips is taking the core design directly from ARM integrating it with other pieces (called IP) like IO controllers, power management, GPU and accelerators like NPUs to make a system on a chip. But with RISC-V lots of Chinese companies have been making their own core designs, that leads to flexibility with design that is not generally available (and certainly not cost effective) on ARM.