I Doubt If This Was Racist
Andrew Sullivan complained about the Jesuits' ban on Jews. I doubt if that was merely a matter of racist antisemitism. It probably had more to do with the explanations that Jews converting to Christianity usually give and how those explanations might have assisted the Protestants.
A typical Jew converting to Christianity will claim that Jesus was the Messiah fulfilling Old Testament prophecies. The only problem with that is there is no hint inside Jewish tradition that the Messiah would be God the Son. It's necessary to read the Bible out of context to come up with that. Similarly, Protestant interpretations of the Eucharist etc. can be obtained by reading the NT out of context but there was no hint inside Christian tradition. The last thing the Catholic Church of that era needed was people in high-profile positions giving sola scriptura explanations.
Come to think of it, maybe we Red-Sea pedestrians should thank the Catholic Church for keeping more people Jewish.