Is anyone else astonished at how much is missing in the hardware and how much is emulated?
The graphics pipeline in modern GPUs are mostly a thin low-level Vulkan/Metal-like layer on top of a massively parallel CUDA-like compute architecture. It's basically all emulated. One of the reasons GPU manufacturers are unwilling to open source their drivers is because a lot of their secret sauce actually happens in software in the drivers on top of the massively parallel CUDA-like compute architecture.
I have signed NDAs and don't feel comfortable going into any detail, other than saying that there is a TON going on inside GPUs that is not "basically all emulated".