Took like 400 years for Christianity to stop being this
Yes, Christianity more-or-less originated at the very tail-end of the "wild cult"-producing era of the Classical civilisation. It did grow up, though, so to speak. And ultimately became the universal religion of the empire.
and it came back to it with some of the crusades.
As I've argued before: those were an outward manifestation of an internal struggle. For its first thousand years, a through-line in Christianity was the Millennium. After a thousand years, Christ was supposed to return. He didn't. It required some re-invention. Christianity stopped stressing the typically Platonist "not of this world" aspects, and started bending towards the more Aristotelian "know the Highest through knowing His creation" take on things. This didn't happen overnight, and I view the Crusades (in large part) as a way of pushing the destructive energy of this internal unrest at an
external target.
It was really quite well done. Islam didn't manage it, and the philosophical effects of this failure on their civilisation can still be seen today. If you want to imagine an ATL Christianity that burned Thomas Aquinas and all the Scholastics at the stake and rejected all rationalism... just look at Islam today. It's a decent indicator of how such a thing ends up.
To say nothing of all the slaughters kicked off by the Catholic clergy refusing to allow anyone to exist outside the pyramid scheme they slowly but surely turned Christianity into
That's a rather anti-Catholic interpretation, and not one I consider fair or honest. To be a bit more nuanced about it; the exact swerve to "material" Aristotelianism that I described produced the Western tradition of science and reason. It was immensely valuable, and as I said: Islam shows us where the alternative route leads. That being said, the turn towards more materialism also led to corruption, decadence and moral relativism. The problem of the late mediaeval and renaissance Church
wasn't that it was ruthlessly opressive (in fact it was very tolerant, as religions go). It was that it was corrupt and stagnant.
The Reformation is in that sense "Plato's Revenge". A return to non-materialist primacy, a rejection of the physical world; that's what the pietism was all about, and what underpinned the iconoclasm. It's not that the dissatisfaction with the Church was unwarranted... but I feel compelled to note that all the modernist ideas that now trouble us stem from the Protestant mind-set. Just as the Catholic position led to problems, so has the Reformation had its own troubling consequences.
{...} until they suddenly were forced to compete for followers from how intensely people were fed up with their bullshit.
I'd like to stress again that when the Catholic Church was firmly in charge, it was actually quite tolerant. Claims to the contrary are mostly cherry-picked exceptions, or Enlightenment-era propaganda that has since been thoroughly debunked.
So the Church wasn't "intolerant until forced to compete". The Church was acually tolerant, until faced with extremely
intolerant Protestantism.
That's what prompted the Counter-Reformation, in which the Catholics became-- well, just as intolerant as their enemies. A sort of race to the bottom, really...
Any overarching authority is going to result in disruptive extremists and corruption.
As indicated above, I only
half agree. Entrenched authority results in corruption.
Chaos and disorder result in extremism.
Religions are extremist when they are in a state of conflict, when they have competition. This is also when they strive for ideological purity. So extremism, intolerance and piety are to some degree linked. When one religion wins and becomes the generally undisputed power, it can afford to be tolerant and fairly moderate. This has the advantage that philosophy flourishes (see: Scholastics), but the disadvantage that it soon invites corruption. Because there are no enemies to "keep you honest"!
The best track record of the 20th century was unsurprisingly the one country who's central government operates on a whitelist of what it's allowed to do and the most thoroughly entrenched separation between government functions.
I'd like to note here that the Western tradition of separation between Church and state and distribution of powers is inherently a Christian legacy, which was formalised all the way back when Charlemagne was crowned by the Pope. For the longest time, the role that the Catholic Church played in politics was, by and large, keeping the Emperor in his place.
Protestantism
harmed the separation of Church and State, by inviting heads of state to also be in charge of state churches. The USA indeed largely esaped this (for a time) by deliberately avoiding a state church. Well done! However, the overall trend of the 'modern' world is still one of unrestrained state power. This is in no small part because the only power that could
check the state -- the Church -- was broken.
The resulting situation sees many people looking for some
alternative to the Church, with very mixed results. Thus, we are in an era of wild cultism... and therefore of ideological "purity wars". Such situations are not stable. Eventually, one religion will win, and become the new (or restored) universal church.
When we look at the various candidates, I feel that a restoration of mediaeval Catholicism would be
far from the worst outcome, really...
