I would agree with you on a broad sense. I think that people across the board are becoming more and more ready to identify as nonreligious, but when addressing the thread topic, I think INFPs are generally more religious than other types.
Some ESTPs would crack jokes at religion, and I think INTPs are likely more skeptical. After reading the thread I came to a different conclusion than you. I think a lot of INFPs are searching for answers to life's big questions, just are unsatisfied with the answers religions give.
Also, I'm guessing that the INFPs that don't use as much internet as we do are much more likely to be deep in religion. When I was in school quite a few of them were in the Bible Club.
Personally, I'm very religious.