For PlayStation APUs, it's likely that AMD presents a menu of options and Sony chooses which components they want. For PS5 Pro, the CPU is unchanged from PS5 because Sony doesn't feel the need for anything faster. A newer CPU would take more area. But Sony really wanted better raytracing and AI so they chose RDNA 3.9 or whatever for the GPU. I suspect the cores are all mostly synthesized so they can support any process and Infinity Fabric is compatible enough that you can mix and match new and old cores.