It seems to me you are the one who is confused. There are two cases, (1) where the port is directly connected to the cpu and (2) where the port is connected to a 'hub' that is connected to the cpu.
He's clearly talking about 1, which is by far the most common scenario, certainly on Macs, and in that case it does require bandwidth and CPU cycles to run at full speed. If you also want that usb-c port to support thunderbolt and all its features you need even more pcie lanes and even access to the gpu.
He's clearly talking about 1, which is by far the most common scenario, certainly on Macs, and in that case it does require bandwidth and CPU cycles to run at full speed. If you also want that usb-c port to support thunderbolt and all its features you need even more pcie lanes and even access to the gpu.