At that point it might as well just be a part of Vitality calculations for tanks though; it adds no choice. As far as I can imagine, the point behind Parry was to give the option of focusing on survival at cost of dps - an extra, tank-specific choice.
They already removed Strength's contribution to RNG mitigation precisely because they didn't want free upward scaling over the course of an installment, and even took free Accuracy out of healer gear. How would free Parry (now increasing chance rather than potency) be any different?