The killer your missing is 'architecture license' versus 'IP' license. The former gives you the right to modify the architecture in your designs (add instructions, non-standard peripherals, alternate memory buses, Etc.) a standard 'IP' license just lets you essentially plop down a standard chip and innovate in the peripherals without touching the system controller at all.
Folks like WD want a processor that is cheap, and specialized like running an error correcting algorithm across spectrum. Generic CPU is too slow, custom CPU is fine. Custom CPU where there is already a lot of other support because other people are using it, is super fine.
Unlimited right to use / modify is a really valuable thing for these companies.