Absolutely.
The point is that in spite of all the “kumbaya” going on between Constantinople & Rome, there will be NO reunion unless doctrinal differences are solved.
That won't happen until the East actually tries to understand what the West is saying in their theological discussions rather than erecting strawmen and burning it down in an encyclical...
5. The new doctrine, that "the Holy Ghost proceedeth from the Father and the Son," is contrary to the memorable declaration of our LORD, emphatically made respecting it: which proceedeth from the Father (John xv. 26), and contrary to the universal Confession of the Catholic Church as witnessed by the seven Ecumenical Councils, uttering "which proceedeth from the Father." (Symbol of Faith).
No effort is made to understand WHAT the Romans say here. Just the mere words is enough to send the East into a tizzy... When the East and West spoke on such issues, such as at the Council of Florence, the East found out that the West CONTINUE to believe there is only ONE PRINCIPLE and that the Filioque is refering to the Divine Economy, which the East ALSO believe is a sending by the Father AND Son (which the Scriptures also agree with). The Filioque is not an expression of what occurs WITHIN the Godhead, as the context of the Creed is NOT speaking about the Godhead, but of the Economy. This problem is not over differing theologies, Your holinesses, the Patriarchs of the East.
Once the East understands that people can use different words to express the same truth, we might get somewhere with a reunion. The Nicean Creed ITSELF was subject to development, for heaven's sake. It is not the final "say all" of our faith... For example, not a word is said about the Eucharist. Many would argue that the Eucharist IS the expression of the Church's unity. But not a word??? No, the Nicene Creed is not the "do all, end all" expression of our faith.
Regards