But it has changed! While I would not characterize the popes in the first millennium as rulers, they were, even in the East, more that just the elder patriarch. The councils themselves are filled with examples of the popes being addressed as the shepherd of the entire church. Protestations by the Orthodox to the contrary will not change the historical facts.
But that means a lot in the East! He is like the father to the younger brothers. He is ultimately responsible for all of them.
The councils themselves are filled with examples of the popes being addressed as the shepherd of the entire church
In a conciliar manner, yes. In fact he is the medium of conciliar unity.
Protestations by the Orthodox to the contrary will not change the historical facts
The Orthodox will treat him as they have before the Schism. A Patriarch has a lot of pull. The eldest patriarch of course has a lot more pull. But the Orthodox will not agree for the pope to pronounce dogma by bypassing the Synod. The General Synod has to infallibly approve. and he infallibly proclaims it.