I'm actually amazed that you were able to get an IHV to give you that access.
Interestingly, most console developers currently have this sort of access. If they are just targeting consoles (or better, a specific platform), they're able to get a lot done. The tricky part is if they have to target PC and consoles. They have the access they want on consoles, but can't replicate on PC.
Actually, on top of that, replicating that task on PC would mean giving developers a nightmarish mix of varying, quirky architectures to target. Realistically, what most _engine_ devs want on PC are more current and lower level access APIs (DX12 and Vulkan) and maybe even an OSS shader compiler. The compiler wouldn't be even for them to poke at. I think they'd hope that the OSS community might do a better job than the IHVs at maintaining the compiler.
Interestingly, most console developers currently have this sort of access. If they are just targeting consoles (or better, a specific platform), they're able to get a lot done. The tricky part is if they have to target PC and consoles. They have the access they want on consoles, but can't replicate on PC.
Actually, on top of that, replicating that task on PC would mean giving developers a nightmarish mix of varying, quirky architectures to target. Realistically, what most _engine_ devs want on PC are more current and lower level access APIs (DX12 and Vulkan) and maybe even an OSS shader compiler. The compiler wouldn't be even for them to poke at. I think they'd hope that the OSS community might do a better job than the IHVs at maintaining the compiler.