As far as I am aware if you license ARM you are not just getting the information to put an ARM core with an ARM instruction set in your system, you can also add

As far as I am aware if you license ARM you are not just getting the information to put an ARM core with an ARM instruction set in your system, you can also add custom instructions to access custom silicon that's in the same package (I think the Wii did that to an extent with their DRM). That way you can add your own very high performance and specialized extensions that might normally end up being separate custom silicon IC's. Compare this to the generally available RISC-V cores which would be not specialized towards some end but allow you to program them as a more general device cooperating with a larger system. This I feel is more apparent in SoC circumstances.