You can assert whatever you like, but the question is whether you could back it up like I did with this article. Some new atheists were certainly smug, but they needed to be self-confident because they were going up against millions of angry, militant Islamists (after the 9/11 attacks), and also against the scary, proto-Trumpian Christian fundamentalists.
What's sanctimonious in Catholicism is leaning on the fallacies I exposed here, fallacies that were centuries in the making. It's a question of providing excuses for the grotesque nature of your institution's history.
The Church slammed together Jewish monotheism with polytheistic Greco-Roman philosophy. Now, if the Church had kept humble about the necessary artistry of that endeavour, that would have been admirable. Instead, to keep its mystique and worldly power, the Church pretended it was only doing God's bidding, that everything the Church does in its official capacity is divinely sanctioned, not a mere human fumbling.
And the Church leans on its stitched-together traditions to bash outsiders like homosexuals, divorcees, and atheists. It's obnoxious, but it's perfectly foreseeable since Jesus's worldview was countercultural, whereas the Church became a worldly, imperial institution.