Only if certain other conditions are met. The PCB routing and cable do not have to not be tightly coupled differential pairs (this is almost never seen in prac

Only if certain other conditions are met. The PCB routing and cable do not have to not be tightly coupled differential pairs (this is almost never seen in practice). The data you’re trying to transmit falls within the line code. Keep in mind only 1/4 of all possible bit sequences are even available in 8b/10b.