I think it's more inertia than anything else at this point. For example, the Xbox/Windows GDK allows you to basically target one codebase for both platforms (w

I think it's more inertia than anything else at this point. For example, the Xbox/Windows GDK allows you to basically target one codebase for both platforms (with minor differences). So developing an Xbox-competing console is a matter of shipping a GDK-compatible software platform. Maybe even using Proton on a linux-based console. But that's just on the software level of course. The entire ecosystem of a console is hard to replace. I would have said it's about preserving the price-point/entry-barrier of the devkits themselves, but they don't cost thousands of dollars as they used to either. So, I think they do the NDA because that's the way it's always been done.