Of course some of them were corrupt. All men are.
But the disappearance of Calvinism and Puritanism as paths that people follow show that ideas can be corrupt as well.
Perhaps you haven’t heard of the resurgence of Calvinism...
Well ... the problem is, of course, that "ideas" are no more God than any church is.
In fact, judging by the typical contents of the "Reformed theology" threads that get posted here, and the various "-isms" railed against therein, the chief contribution of Calvinist thought to the modern Church seems seems to be a tendency to splinter by pushing "wrong-thinking" Christians away.
I don’t understand what you mean by “the disappearance of Calvinism and Puritanism as paths that people follow.” Are you saying that there are no longer people alive who honor the contributions of Calvin and the Puritans? Are you saying that there are no longer any Calvinists alive?
About 70 Million people worldwide, are not exactly a "disappearance."