I think it would be helpful if you broke this down to several topics.

On the point about the "civil right" to believe things not taught by the Church, I don't see a problem with that for Traditional Catholicism. "Civil" places such a right firmly in the realm of the world outside the Church. We certainly cannot claim a right to punish people for holding other beliefs.

Where the modern Church has stumbled, however, is to expand that right to hold other beliefs to claim that we do not have a right to point out that people do not have Salvation if they hold to those other beliefs, and that is what is happening in the interfaith/ecuмenical movement.  For Catholics to point out that someone else is going to hell is not the same as sending them there. They have a civil right to go there. They do not have a civil right to force us to ride along.