That is not what “3/5 of a man” was about. It was about state representation for people who could not vote. The slaveholding states wanted their slaves to be counted in the census for purposes of appointing congressmen. The free states wanted slaves not counted, since they couldn’t vote. The compromise was to count them at 60% (3/5). It was intended to benefit slaves, not to say that they were less than human.
Yes,I understand that strictly speaking you're correct.I was making a more general point regarding how badly our Supreme Court has ruled...on more than one occasion.