3.1 Gen 2 is 10gbps USB + DisplayPort and DisplayPort doesn't mix -- out of the four high speed lanes it either gets two or four lanes. Now full USB 4 is a 40gb

3.1 Gen 2 is 10gbps USB + DisplayPort and DisplayPort doesn't mix -- out of the four high speed lanes it either gets two or four lanes. Now full USB 4 is a 40gbps bus with mixed PCI Express, DisplayPort and USB packets. It is not a small change.