That's a circular argument. The reason $PROTECTED_CLASS became a protected class is because people saw the unjustness of their treatment and agreed that they needed to be treated equally, backed up by the force of law. If you were placed in the year 1800, by your logic you'd be saying that $FUTURE_PROTECTED_CLASS doesn't need to be treated equally right now because they're not a protected class. Clearly, that's not valid. The unequal treatment is the problem; not being in a protected class is irrelevant to that.