I’m a grad of an evangelical school (Calvin), but now consider myself mainline, progressive Christian. My husband is a grad of an evangelical school as well, but received his PhD from a Big 10 U.
Regarding evangelicals in the Ivies, it’s my observation through the years that evangelicals in some of the sci-tech fields are more likely to become faculty in “elite” schools rather than those in the contextual (humanities, social sciences) fields. As mentioned above for example, evangelicals have found a home at MIT. In fields where a hypothesis is proven or not, data is recorded–those areas of study can, but certainly do not always, lend themselves to binary or black/white thinking. In that framework, it is easier to hang on to more conservative, evangelical modes of thinking where there are precepts or beliefs that are never examined, never questioned.
Speaking from our own experience in grad education in the humanities where things are always black or white and grey is recognized as a valid option, when you start to examine one’s own preconceptions in order to gain a wider perspective, previously-held absolutes can shift as you get outside the evangelical bubble. For myself, I didn’t leave faith behind, just hopefully had a bit clearer idea of what actually was a matter of faith and what was more a matter of culture.
I wouldn’t say that there is an “agenda”–other than to teach students to think for themselves and be open to new information that maybe just won’t fit their preconceptions.