Well, the Enlightement is not a monolithic reality. My dissertation is on this subject. I’m right in the middle of researching it. The Scottish/English enlightenment, the German enlightenment, and the French enlightenment all have their particular takes on religion; the German being the most positive I think. So the question, did the enlightenment KO Christianity?
No, it did not. Did it harm Christianity? Some aspects of the enlightenment did and some did not. In fact, its possible to argue that some aspects of enlightenment were the necessary fruition of Christian teaching on the value and dignity of the human person. Our concept of natural rights, an enlightenment concept is Stoic and Christian in origin. The idea of the intrinsic equality and dignity of all people is Christian and Stoic in origin, but came to fruition in the enlightenment. Also, modern empirical science made some aspects of the old scholastic theology difficult to accept. So, a number of thinkers, in the name of enlightenment, sought to provide a new metaphysical grounding for Christian theology. Overall, I think that the principle error of the enlightenment was its excessive optimism. It was excessively optimistic in its view of progress and in its view of the capabilities of the empirical sciences. But that all persons should live as rational, autonomous persons with inherent dignity and rights is the great gift of the enlightenment.