"Because the west was far more plunged into the Dark Ages due to Germanic invasions than the east, the Pope took on the role of emperor in a sense. The eastern practice of collegiality among the episcopate is the more original practice."
This point has come up before.
The Latin Church is centralized unlike the Orthodox for two reasons.
1) There was only one Patriarch in the Latin West.
2) Rome has never granted any of its major daughter Churches true Patriarchal status (such as possessed by Moscow vis-a-vis Constantinople, and unlike the Petit Patriarchs of Serbia or Romania).
The Church of Rome formerly had other major Apostolic sees in the West to relate to such as Carthage and Toledo. However, the Islamic catastrophe (and also the German invasions) utterly destroyed the Church in those regions. Subsequently, every Church in the West not already subject to the jurisdiction of Rome by the Nicene Canons was created subject to them in accord with the Canon of Constantinople I that the Churches among the barbarians are in the jurisdiction of the Patriarch who evangelized them. Since Rome sent out the evangelizers of the Irish, English, Germans, Czechs, Poles, Croats, Hungarians, Scadanavians, Balts, Mexicans, South Americans, etc., quite rightly by the canonical order the Orthodox recognize, did the Pope come to be the Patriarch of all these peoples.
OTOH, when the Patriarchate of Antioch reunited with Rome in 1724, the Pope did not subject the Melkites to his own Patriarchate, but rather maintained them in their privileges.
The Pope's modern role in ruling so many does not come from being a quasi-Emperor, but from strict canonical order.
Now as to Eastern collegiality - this obviously had its limits given the pretensions and civil role of the Patriarch of Constantinople, both under the Empire and the Caliphate. For this reason, the Patriarchs of Antioch, Jerusalem, and Alexandria came to live at Constantinople, and for this reason the Melkites were induced to drop their traditional liturgy for the use of Constantinople (just as Rome did to Spain and Gaul). The modern discovery of Orthodox collegiality would have been quite foreign to these medieval Patriarchs with their centralization of authority in the East.
If the Roman Church really believed that the Melkite Patriarch of Antioch was a real "Patriarch of Antioch and all the East" due all the ancient privileges of that see, they wouldn't have a Maronite holding the title of "Patriarch of Antioch and all the East," and wouldn't have maintained a Latin Patriarchate in Antioch deep into the 20th century, nor would they have a Syrian "Patriarch of Antioch and all the East."
In fact, if, as the Maronites claim, they have been in continual communion and obedience to the throne of Rome from the time of the Apostles, the Roman Church wouldn't have recognized the Melkite schismatics, but rather would have told them to go under the Maronite hierarchy back in the 1700's, since the Maronites laid claim to having the "real" Patriarch of Antioch.
I am no expert in the intricacies of Near-East ecclesiology, but I think I can spot callous opportunism when I see it. Kolokotronis probably knows much more about "the reunion of the Patriarchate of Antioch with Rome" than I do. He also knows at least a little more of the history of how the Eastern Patriarchates survived Ottoman rule. I will leave further comments to him, should he be interested in making any.
According to the most recent papal encyclical that I have read on the subject, Rome still has all the escape clauses necessary to be allowed to intervene unilaterally in any "independent" Eastern Catholic "Patriarchate." And what measure of independence that actually does exist is, for most of the Eastern Catholics, very recent (for all practical purposes, post Vat II.)
Whatever may have happened in the Orthodox East under Ottoman rule, it was reversed when the combination of Greek independence and growing Russian influence in the Middle East gave the Ottomans something else to think about. Whatever violence may have been done to the practice of conciliarity and equality of bishops during Orthodox history, the principle has remained a firm part of our heritage that is undeniably alive and well.
If your point is that the only reason that the Orthodox are conciliar is that we don't know our own heritage (quite a familiar theme, that), then I have to say that it is a non-starter.