I think you're (OP) conflating religion itself (the Church) with how its adherents might carry themselves as its members. It reminds me of the common argument that there is something wrong with the Church and religion because there are clergy members that do bad things. I don't get that. Specifically, I'm going to look at it within the scope of an orthodox (small 'o') Christian conception.
I think that idea has two problems: (1) It could simply be that the clergy members are simply being hypocritical, but hypocrisy has no bearing on the truth of the hypocrite is purporting yet failing to adhere to and (2) it could also be that the clergy are not simply being hypocritical but actually hold heterodox beliefs themselves.
Notice: I limit the discussion to priests, but it applies to laypeople just as well.
In the first case, the priest might actually be espousing orthodox Christian doctrine, but they simply fail to live up to it. Kind of like do as I say, not as I do. If Joe were to go around saying that murder is morally reprehensible, and then Joe goes around murdering people, Joe's hypocritical actions have no bearing on whether or not murder is or is not morally reprehensible. The only thing that evidence goes to show is that Joe is a murderer. Christianity seems to actually leave room for this since every one of us is a sinner--clergy included. Sinning, and the subsequent realization of hypocrisy, just goes to show how we are still human. Christ is the only one that has ever been completely and wholly free from such hypocrisy. That doesn't mean that we shouldn't try to not be hypocrites or that the path itself is flawed.
In the second case, there doesn't have to be (but still can be) hypocrisy. This case deals with a confused understanding, more or less. The priest here paints heterodox beliefs as orthodox Christian doctrine, and it might even be pretty similar. However, the heterodox beliefs lead to actions which appear corrupted--and they are. It is not the Christian faith that is corrupted at that point, though, but they have corrupted the idea of Christianity to posit something (or things) that is (or are) contrary to orthodox Christianity. They haven't corrupted Christianity itself. Nevertheless, they have a corrupted idea of Christianity. The fact that it is corrupted turns it into something new and entirely distinct.
Furthermore, God said the gates of Hell will never prevail over His Church, and I take that to mean that His Church is incorruptible. That doesn't mean that people and their individual conceptions of the Church are free from corruption, though, be they a lay person or the pope (sorry papal infallibility). We can account for some degree of free will (which I'm not going to unpack further) and corruption with God knowing this to be true. If God chose the best of all possible worlds, then it is perfectly possible that we, as agents, can corrupt ourselves while He knows that at least not all of us will and that His Church will persistently prevail. So this Christian notion also seems to deny that Christianity itself can ever become corrupted.
So, with that, I also that think your scope is way too big. There are plenty of distinct Christian denominations out there, and each one claims to have it right. Now if they're all corrupted/wrong, then your scope is fine, but I don't think you can figure that out until you look at all of them. You also have to know what uncorrupted Christianity is to identify it, and people have different measures for that. Obviously I, as an EO, tend to think that we, at least, are both one real measure of incorruption and one part of the incorrupt Church, if not the only measure and part. Additionally, I also think that anyone positing a negative gap in right Christian belief, say between the Early Church and the Reformation, is claiming that the gates of Hell prevailed against the Church at least during that time frame, which I think is problematic. As an aside, I'd also like to note that does not mean I think that all non-EO (non-Christians and atheists included) must go to Hell, and I also don't think it means that EO are guaranteed entry to heaven.
To piggy-back off of Raze as well, I don't think that dogma is a full expression of God and, therefore, of love. It is our attempt, as guided by the Holy Spirit, to create an orthodox Christian context that adheres to revelation. It neither adds nor subtracts to revelation. At best, it can only clarify what has been has been revealed. It is the attempt and desire to remain incorrupt, which I happen to think is motivated by love.
Now, do I think that scholasticism can (and invariably does) lead to corruption? Hell yes!
was born. 
Could you elaborate?
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