Take a look at that again. There's one queue per type. One queue for graphics, one queue for compute, and one queue for DMA. Note that multiple threads are all feeding the single graphics queue.
Yeah, I understood that. One queue per independent type of tasks. But Vulkan diagram didn't mention even that. May be such parallelism is AMD specific, and Vulkan being more generic has to cater for the wider range of GPUs. Not sure.
It shows that multiple queues can be used for one GPU. I guess Vulkan can allow the same but it's not clear from that diagram.