53 out of 63 research studies found that belief correlates negatively with intellignce.
There may be an element of self-selection here, where people that tend to react instinctively are more drawn to religion (and demagogues like DTrumph) while people with more intelligence may be drawn towards education and learning about options for intellectual pursuits.
I think this is a trend these days where science denial is seen by some as a positive opinion, but in the past being educated and intelligent was revered even in church.
This would explain the people mentioned by Faith in Message 3:
There have been too many religious people who are also geniuses for that to be true. Jonathan Edwards, Isaac Newton, John Owen are a few.
Of course they could be outliers in the studies, not enough of them to affect the data.