My feeling is: The real corruption of Dhamma is happening in our own hearts. Maybe that is a huge platitude but i feel that all this searching for a one and only pure or true Dhamma, and all this propagating of a one and only pure Dhamma is itself a form of corruption. This is not to accuse someone. I always sense it is defiled with hate and greed, because what one seeks is not Dhamma but grip. They build a system of thoughts upon stuyding the texts. The sense of grip and order that is created, does cool them down. They feel they now understand Dhamma. They enjoy in the intellectual clarity like people in science who enjoy the beauty of formula’s.
They have a consistent picture in their head in which all pieces of the Dhamma puzzle fit. But it is also idiosychronic. The chooses one makes are solely subjective, rooted in emotions, will, longings, but that they will never ever admit. They feel there idiosynchronic Dhamma-thought-system is pure objectivity. This becomes with years stronger and stronger, especially when others enjoy the clarity of this thought system.
I do not want to accuse anybody but this is how i feel when people are propagating a pure Dhamma, a real understanding. Ofcourse they themselves never corrupt Dhamma, always others.
But for many it is attractive. The brain likes order and such people deliver a certain intellectual order and grip on Dhamma. But it is also very vulnarable to rely on this sense of order and thought-system.
I do feel the order of the mind of a Buddha is not based upon such intellectual grip and system but on letting that go.