Another cause: the papacy. I wonder why Protestants didn't think that the Church needed an earthly vicar to, er, watch the store, like the pope, coming from the Latin pater, the FIRST pope being St. Peter, from the Latin "petra," or rock? Simon Bar Jonah. A.K.A. St. Peter.
Perhaps there's also some lacking in venerating Mary. We venerate saints and WORSHIP God. I think some Protestants might even think we worship Mary. That shows how little they know about the ancient Jewish culture where the son's mother held a lot of influence in the home.
Also there is the "high" and "low" Anglican church: https://gotquestions.org/high-church-low-church.html
That sounds like high and low Mass to this Catholic.
MAYBE the Anglicans have seen the conversations and meetings between the Roman Catholic Church and all the Orthodoxies and thought that a good idea. Talks can't hurt.
Edicts, yes; talks, no.
Regarding Mary: there is no question that she is to be honored, loved and respected. She is Jesus' earthly mother and holds a place that no other person holds. The problem is that the RC religion has elevated her as our mediator and co-redemtrix. All the crazy RC religion doctrine in the world will not change what non-Catholics see, which is that the RC religion worships Mary. If it walks like a duck, quacks like a duck ....