I'm violating my own standard here; but surely you realize that the Protestants built UPON Catholicism - merely minus a lot of the false baggage that had crept it.
Martin Luther was sincere in his first rebellion against the Church. It was not until he actually witnessed the fruits of his labours that he realized what he had wrought. Same with Zwingli. I do not have that opinion of Calvin. I believe that he differed little from Mohammed and Smith in intentions, but only in specific theology.
Sincerity does not faze me.
How accurate were the charges?