That large sections of the Eastern Church were under the domination of Muslims might have a little something to do with the limited evangelization.
I agree. However, a large swath of Europe was under the domination of pagan Northmen and Spain was under the domination of the Muslims during the same period.
For a key period as well, Southern France was dominated by the nihilist Cathari.
Eventually, all three areas were Christianized.
I'm not trying to denigrate the East - simply pointing out that its Christianity is not any more authentic because of its isolation, its long association with the Roman Emperor or its cultural tradition.
i was making an argument in favor of the antiquity and authenticity of the Western Church and its practices.
Catholics are very tired of the argument: "If Easterners do it, it's more traditional, more authentic, more apostolic."
That's not a valid assumption.