Fr. Taft is truly an amazing and most scholarly Eastern liturgist (no wonder, him being a Jesuit - they make great friends but very bad enemies!

).
What is to be most admired about him is his grip on the realities of the Eastern Catholic Churches. He has taught clergy from a wide variety of EC and Orthodox Churches, so he has had first-hand exposure to those issues.
I particularly stand in awe of his understanding of the Calvary suffered by the Eastern Catholic Churches of Eastern Europe, and the Ukrainian Catholic Church especially. He minces no words and calls a spade - a spade.
He also has no fear in defending the EC Churches in an age where Roman Catholic and Orthodox scholars have united in their agreement to dismiss them as relics of a bygone, colonial age. The suffering of the EC Churches never does get discussed in Catholic-Orthodox meetings (which are held without the presence of EC theologians, for the most part “They are talking about us, without us” as Fr. Prof. Andrij Chirovsky of Ottawa has said).
Fr. Taft is an Eastern liturgical purist. That means that he takes seriously the papal motto, “Nec plus, nec minus, nec aliter” when describing EC liturgical usage (I believe it was Pope St Pius X who said that, did he not?).
That the pope is commemorated in the diptychs does not mean that the EC church in question is “uniate.” For him, “uniatism” is a mind-set that exists as much among RC’s and Orthodox as it might among EC’s.
It is a way of viewing Eastern Catholic Churches, as Latinized appendages of the Roman Catholic Church which slavishly reproduce Latin theology with an overwhelming dose of Latinized liturgical/private devotional praxis. Roman Catholics and also Orthodox are guilty of this “uniate” perspective when they see the EC Churches as more of an embarrassment to them both (for Roman Catholics, an embarrassing reminder of the defunct uniate model of the reunion of East and West or “poaching,” simply put; and as for Orthodox, an embarrassing reminder that years of repression under the Tsarist and Soviet systems where the Russian Orthodox Church predominated could not eradicate the EC people’s loyalty to the Greek-Catholic Church and traditions).
The Eastern Catholic Churches have and live their own lives. They possess their own inner liturgical and ecclesial dynamic which is hardly ever closely examined or appreciated by mainstream Roman Catholics and Orthodox.
Fr. Robert Taft SJ stands out as an exception to the rule, however, as do others.
The only real way to oppose uniatism is for the EC Churches themselves to live their own lives as such. Only until they fully regain their consciousness as Particular Churches will uniatism be put to rest (and I don’t believe we can judge the “Easternness” of such Churches on the basis of which Latin-originated practices they keep or discard - much like trying to study traditionalism in Judaism on the basis of the number of Liberal Jews who attend synagogue with prayer shawls . .).
Uniatism will not be put to rest by more meetings between RC’s and Orthodox.
In fact, such meetings only serve to promote uniatism, since their discussions about past relations between those Churches never include Eastern Catholic participants.
Alex