It was, indeed, and was not even particularly dark in certain parts. It tended to be in Britain, and so Bede stands out, etc.
It was also an age of those who confessed a Faith, in the particulars, that is identical to those you apparently and routinely mock as 'schismatics'. Yet your distaste for genuine schism does not seem to be shared by His Holiness, who seems to have done everything he can to deny that the Greek Orthodox are schismatic, even to the point of casting doubt on whether The Church, or at least 'new church', this present institutional church, still recognizes the existence of the Eastern Catholic.
SSPX is a genuine schism. Its bishops, each and every one of them, have been actually excommunicated. John Paul II said so in his 1988 ruling. The Catholics of the Age of Faith werre in communion with the Holy See. The SSPX schismatics are obviously NOT in communion with the Holy See as ruled by the Holy See. Therefore the faith of the schizzies, whatever it may be, is NOT Catholicism.
As to the Eastern Orthodox, arguments from alleged moral equivalency will not make the SSPX schismatics one bit less schismatic than they obviously are and have been ruled by the Supreme Pontiff to be. Opinions of schismatics and excommunicated bishops notwithstanding, John Paul II is pope and an outstanding pope at that. Luther pretended to be Catholic for some time after his apostasy, too, but that did not mean that his self-definition ought to have been accepted by Holy Mother the Church. Not necessarily relevant except in response to those who seek to justify their schismatic campaign for the SSPX package of delusions and falsehoods by appeals to non-existent moral equivalence.
The Roman Catholic Church is the Roman Catholic Church and always will be. We have that on the authority of Our Savior Himself. The SSPX schism of chronic taste-offended malcontents and anti-papal rebels is not. Nor are the Utrecht cult. Nor are the "Old Catholics." Nor are the entire stew of self-appointed schismatic and/or heretical authorities who have been trying on one complaint or another to tear down what Jesus Christ built upon Peter. Cults ie at their own pace. SSPX is no exception.
Since Eastern Catholics ARE in communion with the Holy see, I would venture a guess which is obvious that Rome recognizes our Eastern rites.
As to the Eastern Orthodox, John Paul II has been busily attempting to heal that schism (which would not have been possible as a goal without it being a schism) since he was chosen by the Holy Ghost and the Conclave as the Successor of Peter and Vicar of Christ on Earth. This is a good thing and a lot more sensible effort than trying to reconcile the red hot Marcellian revolutionaries who despise this pope above all others for disciplining them and their excommunicated ringleaders.