Fair enough, but the implication that the Roman Catholic Church is monolithic is a false one. There are many, many factions within that institution which render that argument null & void.
There a set of core beliefs which all Catholics hold, defines being Catholic. Start with the Nicene Creed. After that there are all kinds of ways to worship. There are other teachings which in good conscience you may or may not choose to follow.
We hold to all the catholic creeds.
Liberation theologians, abundant in the RCC, use the language of Catholicism but don’t mean the same thing. They’re not Roman Catholic, yet enjoy it’s communion. Same for other sorts of liberals. There are factions within the Church who render the “you Protestant disagree” argument null & void.
