My belief based on my reading is that the East-West Schism was not a one-time event. It was a gradual development due to hard-headed and hard hearted people on both sides.
Intermittent communion between various Orthodox patriarchates and bishoprics continued all the way until 1729 when Pope Benedict XIII solidified the schism in the Patriarchate of Antioch.
I’m a Melkite, so I know a bit of this history.
The Greeks in Constantinople retaliated by decreeing that all Roman Catholic and Protestant baptisms were invalid.
This article was written by an Orthodox priest, not a Roman Catholic.
Yes, of course the history was more complicated, although there were a few basic points on which there was disagreement.
“Filioque” in the Nicene Creed.
Emperor vs. Pope.
Significant to my mind is that the Roman Catholic Church is decidedly a world church, whereas the Orthodox Church has pretty much been confined to the East, with a few rather thin branches in other places.
But for the most part, the Catholic Church has said that the Orthodox Church is, well, orthodox and has an apostolic succession and legitimate sacraments. Just a few minor disagreements and refusals, which, unfortunately, have persisted.