Note the difference between trusting science, and trusting scientists. Kind of important.
I haven’t read the paper in question but here is the question from the General Social Survey on which its “key finding” apparently is based:
166. I am going to name some institutions in this country. Some people have complete confidence in the people running these institutions. Suppose these people are at one end of the scale at point number 1. Other people have no confidence at all in teh people running these institutions. Suppose these people are at the other end, at point 7. Where would you place yourself on this scale for: k. Scientific community?
Note the wording of the question, which stresses attitudes toward “the people running these institutions.” It doesn’t ask whether you think science has changed. It’s specifically asking about the folks wearing literal and figurative lab coats who are running joints like the National Science Foundation, testifying before Congress, appearing on The Tonight Show while forecasting famine up the ying-yang and praising coercive population control measures, and who often end up being totally wrong about everything.
If it’s “educated conservatives” who have lost faith in scientists, a fully plausible possible explanation is simply that they recognize what libertarians and crypto-libertarians ranging from Thomas Szasz to Michel Foucault have been pointing out since the early 1960s in works starting with The Myth of Mental Illness and The Birth of the Clinic: That much if not all of what passes for dispassionate scientific discourse is hugely implicated in power struggles that have little or nothing to do with disinterested, true-for-all-times-and-all-places Truths with capital Ts.