If Catholicism leads to Protestantism, Protestantism leads to Agnosticism. Why? For one, because it promotes the idea of reading the Bible. The Reformation was founded on the idea of returning to the source and interpreting it for yourself. Logical in principle, but eats itself in practice.
How do you interpret the Bible? Everyone has their own perspective, so it’s not an obvious question to answer. In doing so, you’ll need to go back to when it was authored, itself contentious and done at various dates by various authors. You’ll need to rigorously debate the original meaning of the later canonized texts and question the canonization while you’re at it. And the fractious societal debate can now occur because the spiritual monopoly held by the Catholic Church has become a religious form of a free market economy. The Roman Leviathan is then dethroned and can no longer enforce uniform doctrine of a previously unquestioned Holy Book, much less hold together a Holy Roman Empire. Speaking of which, the academic genre of biblical criticism started in the heartland of the reformation — Germany.
The study of the Bible led to the study of Aramaic, Hebrew and Greek; the languages that birthed it. So, we went back in time and saw the Bible for what it is; no longer was it the Word of God, but the object of scholarly autopsy. Even among the religious, critical understanding has replaced “spiritual” awe, and is why I suspect that what was once selectively revealed in the grandeur of a Cathedral cannot be understood by modern minds.
To assume more truth leads to more religion, you not only must count on the latter’s validity (which makes one more loyal to something aside from truth), but you then must project the inevitable disagreement of competing versions thereof. If it cannot be enforced into consensus, it is only to trend all of its constituents toward uncertainty.
So, perhaps doubt is not the principle concern here; the beginning of doubt is of precedent consideration: competing certainties —which are heightened after the Catholic veil was lifted and Europe wandered past the curtain. I am suggesting ultimately that “spiritual” concerns (and perhaps all other objects of desire) are subject to a general rule: applying science to mystery leads to undoing of the mystery, which was always the best part.
Yes. Protestantism sowed the seeds of its ultimate demise, but it was inevitable. If you’re a Christian, you have no one to be angry with. There is no one to blame. The curtain was already lifting, Europe only needed to point to whoever was nearest to the rope, i.e., Martin Luther - certainly influential (an understatement), but also just there, and the most human and/or the most active of the many factors to assign culpability. The Reformation was a product of the environment; it takes an ecological approach to see this event and its downstream effects as an over-determined outcome; the ideological climate of the era, politics, culture, technology, and a hundred other self-reinforcing synonyms all acted in concert and served as a unity we could pen as the birth of Modernity. Luther was definitely the product of the Reformation, but so too was he its author.