So Catholics can research, study, and opine all they want - but when the Church pronounces doctrine, that's it - and the pronouncement of that doctrine is headed by the Pope. Bluntly put, no matter what a Catholic believes, to remain Catholic is to obey the Pope. It is not a democracy.
There are several problems with what you say. One is it is not internally consistent. You are right when you say we must "obey the Pope" but obedience is not the same as saying that all opinions regarding theology that a person has must automatically be correct, even if they contradict what has always been believed by the Church. My children must obey me, but that does not mean that I am always right.
Also, to use your phrase, it is just not that simple. Church teaching is not just a declaration to be regurgitated endlessly without any understanding. And, if any Church teaching is to be understood then the hearer must look not just to what has just been said, but to all that it builds on. This is because Catholicism, even more than most other such belief structures, is one of tradition. The Church never teaches without placing it in the context of the historic faith which she has received. If a pope expounds on salvation outside of the Church, for instance, he does so by looking to the historic and constant teaching of the Church, and it is by placing any teaching into this framework that the hearer can properly understand it and act on it. This is what Pope Benedict XVI called a hermeneutic of continuity rather than rupture.
Just look at this thread. People are arguing that it is not possible to disagree with the theological opinions of a pope without ceasing to be Catholic. Is that a Catholic teaching? No, and it never has been. It is the opinion of people who are threatened, for whatever reason, with the possibility that a pope may not be 100% right at all times whatsoever. Perpetual personal papal infallibility is not a teaching of the Church, and yet it comes up over and over again. Why? Because people have no grasp of the historical teachings of the Church. So who is promoting democracy of faith? Those who ignorantly promote these false ideas which have never been part of the faith, or those who know what the Church has always taught and remain faithful to it?
The problem is that you are arguing as if laity opinion is equal to the clergy’s decisions and teachings, and within the Catholic Church, they are not.
That’s why it’s simple, within its complexity. Whatever the laity believes or decides for whatever reasons, they are simply not authorized to decide upon doctrine. They are issued doctrine, and expected to study, understand and obey it. There is a very strict hierarchical division between laity and clergy in Catholicism, and this is the underlying dynamic in this entire issue. Under the guise of research and learning, an implicit claim of authority is being made by (mostly) American Catholics to decide doctrine. This claim of laity authority, implicit or not, quite simply, is not valid within the Catholic Church.
Laity can offer their understandings to the clergy, yes. But the doctrine of the Church is that the clergy will review any such understandings and issue a pronouncement of either conformity and acceptance, or error and correction. And the flow of power is one way - from the top down.
I understand that a lot of people don’t like this situation, especially Americans who grew up with ideas of freedom and democracy. But the Catholic Church is also a vehicle of penance, of spiritual humility and obedience. And it will never, ever surrender its claim to absolute authority in matters it deems its jurisdiction and under its auspices of control. Because without that it would not longer be the Catholic Church.
It’s not the middle ages. If people don’t like it, they can leave. But people who want to stay in the Church in order to challenge its teachings have motives ulterior to being “good Catholics.” The presumption of the Church is that the clergy are more learned and particularly blessed to interpret the true doctrines of Jesus Christ. Accepting that authority is what it means to be Catholic.