The points you make are valid. Rush has said the country clubber type Republicans by in large don’t want to be associated with “the Religious Right”, “the Pro Life” and the “Pro Gun Rights” elements of the Republican Party. They will look down their noses at them, in large part because they fear disdain and ridicule by the intelligensia of society and the PC crowd if it comes to light that they are associated with them. Yes, could be an element of fear and misunderstanding towards them, as you say, but Rush thought it was more wanting to be on the side of what is popular in the media and among the more elite among us, so as not to be identified with the “neanderthals” that comprise that disdained group. Pity.
I think some people who are intellectually insecure are very susceptible to going along with what the MSM defines as “respectable” thought, which means pro-abortion, pro-gay marriage, and anti-religious right. Also, many people’s views of the religious right are almost totally formed by their perceptions of televangelists, which are largely - and understandably - negative. (My apologies to the handful of televangelists who I think are straight shooters, even if I don’t necessarily agree with them, e.g., Charles Stanley, James Robison, and a few others.)