“The Church” back in the days when the Bible was assembled included the spiritual ancestors of all Christians, not just Roman Catholics. The Protestant position is that the official church, by the time of Martin Luther, had departed from its true calling and nature, essentially separating itself from faithful execution of its mission. The church as an organization had departed from the true catholic (small c) Christian church.
The eventual split of the Protestant denominations from the official church organization of the day is seen by Protestants as a return to the true church, a reclamation of the Christianity that existed in the early days, minus the supposedly corrupting institution of the papacy. The official Church of Rome is seen as the body that departed from the true church, at least temporarily.
Catholics see things quite differently, of course, emphasizing Apostolic succession.
Whoever you agree with, I think it’s fair to say that the tension with the Protestant denominations has helped keep the Catholic church honest, so to speak. Catholic Bible studies? These would never have sprung up without indirect pressure from Protestant churches.
