“What I see, however, are, to pick a few examples, accusations of the Catholics being deceived into a cult by power-hungry priests, of ignorance and rejection of the Holy Scripture, and of idolatry.”
Sure, that kind of garbage is exactly the kind of thing that is not constructive -— and takes up 99% of inter-denominational dialog.
There is ample shared theology, and seldom discussed.
But we cannot discuss it unless we have a common platform of mutual respect. For example, a conversion to Catholicism should be treated like a sincere journey of faith of an intelligent human being, not like an impressionable youth being fooled by bells and smells.