, it said that it was repealed and superseded in the 70s.
It absolutely did not say that.
17 U.S.C. § 109(a) from 1976 clarified the earlier laws without changing them at all. It even specifically mentions video games. That is if you buy a video game you have the right to resell it (dispose).
Courts have since ruled that the law and 17 U.S.C. § 109(a) don't apply because you bought a "license".
But that doesn't change the law or 17 U.S.C. § 109(a) which was even clearer that someone who purchases music or a video game has the right to resell it.
Court rulings aren't law.