Eastern Christians do not care much for Augustine’s theology, which means that the gap between them and Protestants is very wide. To conclude there is a radical contradiction between Catholics and Orthodox is to ignore the similarities. Bonaventura is as “spiritual,” as any eastern sage, and a modern Catholic saint, Padre Pio, as mystical as any eastern monk. As for Mary, the eastern respect for theotokos is very deep.
I understand that, and the purpose behind the post was not to postulate a profound salvific separation (unless UNAM SANCTAM may be held to mean so), but that under sola ecclesia there is also a depth of significant divisions.
In addition, under that model, in which the church is the supreme authority, esp. as per Rome in which Scripture, history, and tradition is only what the infallible magisterial office says they are and mean, and are thus defined as supporting them - and which cults like the Mormons effectively operate out of and do - are the greatest deviations from core salvific truths, as well as the doctrinalization of perverse traditions.