One thing people leave out is that there is a LOT to religion and spirituality. Christianity, for example, is not entirely defined in terms of rejecting evolution. That’s just a (tiny) part of their beliefs. When you start in a science-denying religion (worst-case scenario), it’s still only a small percent of your beliefs that contradict the science. So some people stay believers and deny the contradictory science… others stay believers “except the science”.

Many people adhere to non-science-denying religions. So while they are naturally less likely to pick a science major, if they DO pick a science major, nothing in it will knock them out of their faith.