Ridiculous.
Someone should remind him that the RC church was the only thing that stood between Paganism/Islam and the utter eradication of Christianity for a thousand or so years. To think that the Catholic faith could be ‘unchristian’ takes a special kind of self delusion.
Christianity as we know it today (if at all) would not exist without the Catholic church. And I say that as a lapsed Catholic.
Never heard Luther? He thought it was thoroughly corrupt. I personally like Catholics a lot. They think they are the true church. But, I come from a very long line of Irish Catholics and they were all great people.