I think you need to pay attention to what we were talking about? I never talked about Ryzen. Never mentioned it at all. I don't even know why you keep bringing it up even after I already said I wasn't referring to Ryzen or it's support for mGPU.
I think you should read up honestly. Because I stand corrected. These are not meant for gaming which is my original point. They aren't and so far leaked slides haven't shown them to be marketed as such.
But in your view, you need those cores for gaming when using 4 GPUs. Yet the problem with that is 3 or 4 GPUs is not even a relevant argument. I'd say .1% of the market runs that setup. Especially since nvidia dropped support for it last year outside of certain things and hardly anyone bothers with AMD. As for game supporting it, it's basically none. Cpu intensive games will show better results yes, but that's because it's better optimized for the CPU load, which means it takes advantage of more threads which therefore means it's easier for Nvidias driver to better offload the tasks from the first thread onto the others and let them help the distribution of sending the GPU processes. Therefore, it's mostly the driver that nvidia have that actually gives you the better performance under mGPU. But even with that support, the scaling goes down. PCI lanes is not the end all be all of whether or not it works better.