I hadn't realized that the Orthodox Church declared Ecumenical Councils validly led by the Bishop of Rome are no longer infallible. Because this WAS believed BEFORE the Great Schism... Can you point me to an Orthodox Ecumenical Council that made that statement?
The problem here is that you are using "papal supremacy" without defining it. Secondly, you seem to believe that the Church is frozen in time at the year 1054 - that Doctrine developed throughout the first millenium, then stopped at that date. Know that just as the Catholic Church continued to define doctrine after the Nestorians left, or the Armenians left, or the Coptics left, the Catholic Church will CONTINUE to define doctrine after the Orthodox or the Protestants left the Church. Is this surprising?
Regards
Papal supremacy as defined in Vatican 1, as exemplified by the unilateral adoption of the filioque by the bishop of Rome before the 1054 schism is not Papal supremacy as defined in Councils prior to that time.
Further I do not redefine it since if I am talking about the post schism church's standing on the bishop of rome, certainly I am talking about the post schism catholic application of papal supremacy.
The Bishop of Rome was excommunicated and started a heretical church, and innovated doctrine outside that doctrine accepted by the councils. That is the schism, and now amount of surprise or lack thereof changes that.
This really brings to view the whole problem of eccumentical relations; Catholics who would like the assume that the problem is social, or political, and forget the schism ever happened.
Patriarch Alexy II has repeatedly expressed that there can be no healing of the schism until 2 things are addressed; the non canonical uniate church proselytizing in Orthodox areas. No amount of Icon returning, and freindly gestures will change that; The Orthodox church is headed by Christ non a single man, and rejects the false doctrines of the Bishop of Rome.